Handbook of Magnetic Hybrid Nanoalloys and their Nanocomposites 3030909476, 9783030909475

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Sabu Thomas Amirsadegh Rezazadeh Nochehdehi Editors

Handbook of Magnetic Hybrid Nanoalloys and their Nanocomposites

Handbook of Magnetic Hybrid Nanoalloys and their Nanocomposites

Sabu Thomas • Amirsadegh Rezazadeh Nochehdehi Editors

Handbook of Magnetic Hybrid Nanoalloys and their Nanocomposites With 432 Figures and 74 Tables

Editors Sabu Thomas UNISA Biomedical Engineering Research Group Mahatma Gandhi University Kottayam, Kerala, India

Amirsadegh Rezazadeh Nochehdehi UNISA Biomedical Engineering Research Group Department of Mechanical Engineering College of Science, Engineering and Technology UNISA Florida Science Campus University of South Africa Johannesburg, South Africa

ISBN 978-3-030-90947-5 ISBN 978-3-030-90948-2 (eBook) https://doi.org/10.1007/978-3-030-90948-2 © Springer Nature Switzerland AG 2022 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The publisher, the authors, and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. This Springer imprint is published by the registered company Springer Nature Switzerland AG. The registered company address is: Gewerbestrasse 11, 6330 Cham, Switzerland

Preface

Studies on magnetic nanoalloys are one of the most exciting research areas in modern science and technology. These nanoalloys are the stiffest and strongest nanomaterials known, with remarkable electronic, mechanical, chemical, electrical, thermal, and biocompatible properties, and also have potential multifunctional applications in a wide range of fields from industry to medicine. Polymers can serve as an ideal matrix to develop multifunctional nanocomposites. Moreover in the past few years, tremendous advances have been witnessed in the experimental and theoretical studies on various properties of magnetic nanoalloys. Although there is extensive literature on various advanced applications of iron and cobalt magnetic nanoparticles that have already been published in peer-reviewed journals and conference proceedings, till date no systematic scientific reference book has been published specifically in the area of iron- and cobalt-based magnetic nanoalloys. This provides a great opportunity for the future of developing new nanomaterials that can be used in numerous fields such as biomedical areas, environmental remediation, and even in agriculture fields. The growing interest among academics and industrial researchers in the field of material science and polymer technology is the driving force for the presentation of this edited book. Indeed, our book is a cutting-edge multidisciplinary reference specifically focused on magnetic nanoalloys, their nanocomposites, and related aspects. In summary, this book makes an attempt to provide an in-depth study of the state of the art of magnetic nanoalloys, polymer nanocomposites, and their applications. We, Senior Editors, have been working in the field of nanomaterials and nanocomposites for the past few decades. We have very successfully conducted research projects, presented papers in various conferences, contributed papers in peerreviewed journals, and conducted international conferences in the field of nanoalloys and their nanocomposites and application field. We have a wide range of contacts with major researchers and industrialists in this field. The nature of this technical book may serve as a very useful reference book or textbook to a broad range of scientists, industrial practitioners, undergraduates, graduates and postgraduate engineers, research scholars, and (primarily in the fields of nanoscience and nanotechnology, materials science and engineering, surface science, bioengineering, polymer chemistry, polymer physics, and chemical engineering) other professionals, including polymer engineers and technologists as well as chemistry engineers and v

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pharmacists from industries. It is hoped that the proposed book will be highly desired by leading professionals, researchers from industries, academics, and government and private research institutions across the globe who contributed to this book. Almost all the analytical techniques are discussed in the book, and without exaggeration, it will be a first-rate reference for professors, students, industrialists, and scientists. This book will assist them to solve fundamental and applied problems in the synthesis procedure of magnetic nanoalloys and their polymer and ceramic nanocomposites. The book also covers comprehensive characterization and applications. Hereupon, we proposed to bring out a reference book that deals with various fascinating attributes of nanomaterials, their composites with different polymeric materials (both natural and synthetic), and their potential, advanced, and multifunctional applications. As the title indicates, this book aims for a fairly comprehensive review of the recent accomplishments in the area of iron- and cobalt-based magnetic nanoalloys and their nanocomposites. In order to get a clear cutting edge idea about synthesis procedure, properties and characterization techniques, multifunctional applications of iron- and cobalt- based nanocomposites (ICBMN); in this book, we took a closer and accurate look at the scientific literature published so far. We included all the recent advancements in the area of this fascinating nanomaterial. This is the first time such a comprehensive analysis of various potential applications of IBMN has been undertaken to understand the interactions in polymer and ceramic nanocomposites. In this context, the proposed book differs from the titles mentioned in other sources in the market. It is unique in this aspect, and we are fully dedicated to covering a wide range of ICBMN functional applications from industry to medicine. The fundamentals and fascinating attributes of nanoparticles led us to compile this book in two volumes and 43 chapters including theory, principles, and fundamentals of synthesis, modeling and characterization techniques, multifunctional applications and environmental risks. Volume 1 covers magnetic hybrid nanoalloys’ (MHNAs) synthesis and modeling techniques in 16 chapters. It is focused on reviewing the various methods of synthesis, growth, and alloying mechanisms of metallic nanoalloys that shows very high magnetic saturation among the existing materials; including iron, cobalt, nickel, chrome, manganese elements based nanoalloys and their polymer/ceramic nanocomposites. We also discussed the formation mechanism of magnetoelectric multiferroic materials, magnetic carbon nanotube (CNTs) and perovskite materials that are novel class and next generations of the multifunctional nanomaterials. It displays simultaneous magnetic spin, electric dipole, and ferroelastic ordering, and have drawn increasing interest due to their multifunctionality for a variety of device applications. In addition, it covers the synthesis mechanisms of polymer nanocomposites. The volume discusses various chemical, physical, and biological synthesis procedures of magnetic hybrid nanoalloys. Colloidal route, sol-gel, precipitation, polyol, physical, mechanical procedures, vapor and thermal deposition, atom beam sputtering, laser ablation, vacuum deposition, ball milling, melt and direct mixing are discussed initially. Green synthesis protocols including microorganisms, plant extracts, and enzymes, DNA, membranes, proteins, and ferritin

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mechanisms are also covered. Full chapters have been devoted to the theory of modeling and simulation aspects of nanotechnology, nanomedicine, and magnetic properties of materials at nanoscale, which covers the early stages of development of MHNAs. Computational and numerical modeling has also been discussed in detail. Volume 2 covers novel characterization techniques and fascinating applications of MHNAs in 27 chapters. It focuses on various innovative characterization techniques of magnetic hybrid nanoalloys. Morphological, rheological, mechanical, viscoelastic, thermal, electrical, and electromagnetic shielding properties are discussed in detail. The text reviews various classes of characterization techniques such as light and electron microscopy, x-ray scattering, neutron and light scattering, vibrating sample magnetometer techniques, as well as spectroscopic, rheological, XPS, SIMS, and NANo SIMS characterizations. Moreover, it provides an in-depth coverage on thermal analysis, contact angle studies, electrical and dielectric characterization, ageing mechanisms, biocompatibility studies, and diffusion and transport studies of MHNAs. The volume is devoted to introducing various potential applications of MHNAs concentrating on four main application fields, including industrial, agricultural, environmental, and medicinal and biological. The text describes every application of MHNAs, for example, mechanical applications, energy conversion and storage applications, fuel cells and water splitting, solar cells and photovoltaics, sensing applications, nanofluidics, nanoelectronic and microelectronic devices, nanooptics, nanophotonics and nano-optoelectronics, nonlinear optical applications, piezoelectric applications, agriculture applications, biomedical applications, thermal materials, environmental remediation applications, as well as antimicrobial, antibacterial, and other miscellaneous and multifunctional applications of MHNAs. In the recent decades; nanoproducts, in particular magnetic hybrid nanoalloys, have significantly developed. Because of that, it is vital to determine the environmental risks and life cycle of the nanomaterials. Ultimately, the book pursues a significant amount of work on life cycle assessment of MHNAs and toxicity aspects. We are delighted to invite you to read this reference book, and pleased to appeal to you for sharing the valuable scientific and technical constructive criticism. We would absolutely love to hear from you for future collaborations. Kottayam, India Johannesburg, South Africa October 2022

Sabu Thomas Amirsadegh Rezazadeh Nochehdehi

Contents

Volume 1 Part I

Theory, Modeling, and Synthesis

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1

1

Nanotechnology and Medical Applications . . . . . . . . . . . . . . . . . . . Mohammad Irani, Parvaneh Ghaderi-Shekhi Abadi, Leila Roshanfekr Rad, and Mahsa Ebizadeh

3

2

Synthesis of Iron-Cobalt Nanoalloys (ICNAs) and Their Metallic Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mythili Narayanan, Vijayasri Gunasekaran, Gurusamy Rajagopal, and Jegathalaprathaban Rajesh

39

3

Synthesis of Core-Shell Magnetic Nanoparticles . . . . . . . . . . . . . . Sibel Büyüktiryaki, Rüstem Keçili, Ebru Birlik Özkütük, Arzu Ersöz, and Rıdvan Say

65

4

Synthesis of Cobalt-Based Magnetic Nanocomposites . . . . . . . . . . Ginena Bildard Shombe, Shesan John Owonubi, Nyemaga Masanje Malima, and Neerish Revaprasadu

107

5

Synthesis of Cobalt and Its Metallic Magnetic Nanoparticles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nguyen Viet Long, Nguyen Thi Nhat Hang, Yong Yang, and Masayuki Nogami

6

7

137

Synthesis of Mn-Based Rare-Earth-Free Permanent Nanomagnets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Yohannes W. Getahun and Ahmed A. El-Gendy

173

Synthesis of Magnetoelectric Multiferroics and Its Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D. Navadeepthy, G. Srividhya, and N. Ponpandian

203 ix

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Contents

8

9

10

11

12

Synthesis of Magnetic Carbon Nanotubes and Their Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nyemaga Masanje Malima, Shesan John Owonubi, Ginena Bildard Shombe, and Neerish Revaprasadu

233

Chiral Magnetic Nanocomposite Particles: Preparation and Chiral Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pengpeng Li and Jianping Deng

273

Manufacturing Techniques of Magnetic Polymer Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Elif Esra Altuner, Muhammed Bekmezci, and Fatih Sen

303

Vacuum-Based Deposition Techniques to Synthesize Magnetoelectric Multiferroic Materials . . . . . . . . . . . . . . . . . . . . . Arpana Agrawal

319

Advanced Progress in Magnetoelectric Multiferroic Composites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Essia Hannachi and Yassine Slimani

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13

Surface Modification of Magnetic Hybrid Nanoalloys . . . . . . . . . . Bijaideep Dutta, K. C. Barick, and P. A. Hassan

14

Theory, Modeling, and Simulation of Magnetic Hybrid Nanoalloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rimmy Singh

405

Analytical Approaches of Magnetic Hybrid Nanoparticles Using Numerical Modelling and Simulation Tools . . . . . . . . . . . . . . . . . . Nikolaos Maniotis and Konstantinos Simeonidis

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15

16

Computational Techniques for Nanostructured Materials . . . . . . . Riyajul Islam, Krishna Priya Hazarika, and J. P. Borah

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Volume 2 Part II 17

18

Characterization Techniques and Applications . . . . . . . . . .

Introduction of Vibrating Sample Magnetometer for Magnetic Characterization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vineeta Shukla Characterization of Iron Oxide and Doped Iron-Oxide Nanocomposites for Photocatalytic Degradation of Organic Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I. Khan and Ahmad S. Ali

481

483

507

Contents

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Optical Properties of Magnetic Nanoalloys and Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . T. Sujin Jeba Kumar and Muthu Arumugam

20

Electron Microscopy of Magnetic Nanoparticles . . . . . . . . . . . . . . Ahmed Aliyu and Chandan Srivastava

21

Scanning Transmission Electron Microscopy of Magnetic Nanoalloys and Their Nanocomposites . . . . . . . . . . . . . . . . . . . . . . Loukya Boddapati and Francis Leonard Deepak

547 575

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22

Spectroscopic Techniques for Multiferroic Materials . . . . . . . . . . . Arpana Agrawal and Tanveer Ahmad Dar

629

23

Rheological Characterization Tools: A Review Pragnesh N. Dave and Ekta Khosla

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659

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Thermal Analysis of Magnetic Hybrid Nanoalloys and Their Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Debasrita Bharatiya, Biswajit Parhi, and Sarat Kumar Swain

679

Thermal Behavior of Magnetic Nanofluid Within an Enclosure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . M. Sheikholeslami, Elham Abohamzeh, and Ahmad Shafee

699

Contact Angle Studies on Functional Surfaces Containing Magnetic Particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nursev Erdogan and Salih Ozbay

733

Contact Angle Studies of Hydrophobic and Hydrophilic Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Mohammed Danish

761

25

26

27

28

Electrical and Dielectric Properties: Nanomaterials . . . . . . . . . . . . Vijayasri Gunasekaran, Mythili Narayanan, Gurusamy Rajagopal, and Jegathalaprathaban Rajesh

783

29

Diffusion and Transport Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . Elif Esra Altuner, Muhammed Bekmezci, and Fatih Sen

801

30

Oxidation Behavior of Magnetic Hybrid Nanoalloys . . . . . . . . . . . Marjan Nouri

819

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Biological Characterization of Magnetic Hybrid Nanoalloys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Muhammed Bekmezci, Elif Esra Altuner, and Fatih Sen

861

Magnetite–Graphene-Based Composites and Their Potential Application as Supercapacitor Electrode Material . . . . . . . . . . . . . Bhaskar J. Choudhury and Vijayanand S. Moholkar

879

32

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33

34

35

Contents

Iron-Based Magnetic Nanoadsorbents for Organic Dye Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Khadidja Taleb, Nadia Chekalil, and Salima Saidi-Besbes

915

The Impact of Magnetic Nanoparticles on Microbial Community Structure and Function in Rhizospheric Soils . . . . . . . . . . . . . . . . Trupti K. Vyas and Anjana K. Vala

949

Environmental Applications of Magnetic Alloy Nanoparticles and Their Polymer Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . Sonia Bahrani, Seyyed Alireza Hashemi, and Seyyed Mojtaba Mousavi

975

36

Hydroelectric Cell as Source of Green Electricity Generation: Metal (Multiferroic, Iron, Ferrite, Cerium-Graphene)-Oxides . . . . . . . . . 1007 K. C. Verma and Navdeep Goyal

37

Catalysis Application of Magnetic Ferrites and Hexaferrites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1061 Felipe Fernandes Barbosa, Johnatan de Oliveira Soares, Maicon Oliveira Miranda, Marco Antonio Morales Torres, and Tiago Pinheiro Braga

38

Magnetic Iron Oxide Nanoparticles and Nanohybrids for Advanced Water Treatment Technology . . . . . . . . . . . . . . . . . . . . . 1103 Alice G. Leonel, Alexandra A. P. Mansur, and Herman S. Mansur

39

Medicinal and Biological Application of Magnetic Alloy Nanoparticles and Their Polymer Nanocomposites . . . . . . . . . . . . 1127 Gamze Dik, Ahmet Ulu, and Burhan Ates

40

X-Ray Computed Tomography and Magnetic Resonance Imaging Applications of Magnetic Nanoalloys and Nanocomposites . . . . . . 1155 Naim Aslan and Mümin Mehmet Koç

41

Magnetically Retrievable CuNi Alloy as Catalyst for Reductive Coupling of Nitroarenes with 2-Propanol . . . . . . . . . . . 1175 Biraj Jyoti Borah and Pankaj Bharali

42

Photocatalytic Applications of Magnetic Hybrid Nanoalloys and Their Nanocomposites . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1193 A. Manikandan, K. Thanrasu, A. Dinesh, K. Kanmani Raja, M. Durka, M. A. Almessiere, Y. Slimani, and A. Baykal

43

Nanotoxicity and Environmental Risks of Magnetic Iron Oxide Nanoparticles and Nanohybrids . . . . . . . . . . . . . . . . . . . . . . . . . . . 1225 Alice G. Leonel, Alexandra A. P. Mansur, and Herman S. Mansur

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1251

About the Editors

Professor Sabu Thomas Vice-Chancellor, Mahatma Gandhi University Professor of Polymer Science & Engineering School of Chemical Sciences Founder Director, International and Inter University Centre for Nanoscience and Nanotechnology Mahatma Gandhi University Kottayam, Kerala, India Professor Sabu Thomas is currently Vice Chancellor of Mahatma Gandhi University. He is also a full professor of Polymer Science and Engineering at the School of Chemical Sciences of Mahatma Gandhi University, Kottayam, Kerala, India, and the Founder Director and Professor of the International and Interuniversity Centre for Nanoscience and Nanotechnology. Prof. Thomas is an outstanding leader with sustained international acclaims for his work in Nanoscience, Polymer Science and Engineering, Polymer Nanocomposites, Elastomers, Polymer Blends, Interpenetrating Polymer Networks, Polymer Membranes, Green Composites and Nanocomposites, Nanomedicine, and Green Nanotechnology. Dr. Thomas’ groundbreaking inventions in polymer nanocomposites, polymer blends, green bionanotechnological and nanobiomedical sciences have made transformative differences in the development of new materials for the automotive, space, housing, and biomedical fields. In collaboration with India’s premier tyre company, Apollo Tyres, Professor Thomas’ group invented new high-performance barrier rubber nanocomposite membranes for inner tubes and inner liners for tyres. Professor Thomas has received a number of national and international xiii

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About the Editors

awards which include: Fellowship of the Royal Society of Chemistry, London FRSC, Distinguished Professorship from Josef Stefan Institute, Slovenia, MRSI Medal, Nano Tech Medal, CRSI Medal, Distinguished Faculty Award, Dr. APJ Abdul Kalam Award for Scientific Excellence – 2016, Mahatma Gandhi University – Award for Outstanding Contribution – Nov. 2016, Lifetime Achievement Award of the Malaysian Polymer Group, Indian Nano Biologists Award 2017, and Sukumar Maithy Award for the best polymer researcher in the country. He is in the list of most productive researchers in India and holds a position of No. 5. Because of the outstanding contributions to the field of Nanoscience and Polymer Science and Engineering, Prof. Thomas has been conferred Honoris Causa (D.Sc.) Doctorate by the University of South Brittany, Lorient, France and University of Lorraine, Nancy, France. Currently, Prof. Thomas has been awarded Senior Fulbright Fellowship to visit 20 universities in the USA and most productive faculty award in the domain Materials Sciences. He was also awarded the National Education Leadership Award – 2017 for Excellence in Education. Prof. Thomas also won the 6th contest of “mega-grants” in the grant competition of the Government of the Russian Federation (Ministry of Education and Science of the Russian Federation) designed to support research projects implemented under the supervision of the world’s leading scientists. He has been honored with Faculty Research Award of India’s brightest minds in the field of academic research in May 2018. Professor Thomas was awarded with Trila – Academician of the Year in June 2018, acknowledging his contribution to the tyre industry. In 2019, Professor Thomas was selected as a member of the prestigious European Academy of Sciences. Professor Thomas has published over 800 peer-reviewed research papers, reviews, and book chapters. He has coedited 127 books published by Royal Society, Wiley, Woodhead, Elsevier, CRC Press, Springer, Nova, etc. He is the inventor of 15 patents. The H index of Prof. Thomas is 97, and he has more than 44,339 citations. Prof. Thomas has delivered over 350 plenary/inaugural and invited lectures in national/international meetings in over 30 countries.

About the Editors

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Amirsadegh Rezazadeh Nochehdehi UNISA Biomedical Engineering Research Group (UBERG) Department of Mechanical Engineering (DME) College of Science Engineering and Technology (CSET) University of South Africa (UNISA) Florida, Johannesburg, South Africa Amirsadegh Rezazadeh Nochehdehi is Materials Engineer Technologist (CET) accredited by Engineering Council of South Africa (ECSA). He is currently an academic staff at the University of South Africa (UNISA). He is also a PhD fellow at the Biomechanics Research Group, Department of Mechanical and Industrial Engineering (DMIE), University of South Africa (UNISA), Johannesburg, South Africa. He obtained his MSC.Eng in Biomedical Engineering – Division of Biomaterials in 2017, from Materials and Biomaterials Research Center, Iran. He received his BSC.Eng in Materials Engineering – Division of Industrial Metallurgy in 2012, from Karaj Branch of Islamic Azad University, Iran. As a research scholar, he worked in polymer nanocomposites for tissue regeneration applications at International and Inter-University Center for Nano-science and Nano-technology (IIUCNN) in Mahatma Gandhi University (MGU), Kerala, India, in 2018. He also worked in magneto-metallic alloy nanoparticles at Nanotechnology Research Center at the University of Zululand, South Africa, as visiting researcher in 2017. He is a detail-oriented Executive Biomedical Science and Engineer. He is also an accelerated Metallurgist and Materials Engineering Technologist with over 10 years’ experience in research and development, quality management system (control and assurance), regulatory affairs, safety engineering, and inspection, at the time of publishing this book. He was quality and safety engineer inspector while working at Tehran Urban and Suburban Railway Operation Company (TUSROC) for a period of 5 years. He is an R&D specialist and scientific projects engineer who works in the field of materials specifications, advanced materials, materials and nanomaterial fabrication, nanoscience and nanotechnology, nanomedicine, nanomaterials,

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About the Editors

nanocomposites, magnetic nanoparticles and nanoalloys, magnetic hyperthermia, nanomaterial in cancer diagnosis and treatment, biomedical science and engineering, bio-materials, 3D printing biomaterials, biomechanics, mechanics of tissue, soft tissue biomechanics, mechanical modeling, cartilage mechanics and joint preservation, and regenerative medicine.

Section Editors

Yves Grohens IRDL-CNRS Laboratory Université Bretagne Sud allée Copernic, Ploemeur, France

Józef T. Haponiuk Polymer Technology Department Faculty of Chemistry Gdansk University of Technology Gdańsk, Poland

Nandakumar Kalarikkal School of Pure and Applied Physics International and Inter University Center for Nanoscience and Nanotechnology School of Nanoscience and Nanotechnology Mahatma Gandhi University Kottayam, Kerala, India

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Section Editors

Fulufhelo Nemavhola Unisa Biomedical Engineering Research Group Department of Mechanical Engineering School of Engineering University of South Africa Unisa Science Campus Pretoria, South Africa

Contributors

Parvaneh Ghaderi-Shekhi Abadi Environmental Health Engineering Research Center, Alborz University of Medical Sciences, Karaj, Iran Non-communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran Elham Abohamzeh Department of Energy, Material and Energy Research Center (MERC), Karaj, Iran Arpana Agrawal Department of Physics, Shri Neelkantheshwar Government PostGraduate College, Khandwa, India Ahmad S. Ali Department of Physics, Faculty of Science, Al-Azher University, Assiut, Egypt Ahmed Aliyu Department of Materials Engineering, Indian Institute of Science, Bangalore, India Department of Chemical Sciences, Federal University Wukari, Wukari, Nigeria M. A. Almessiere Department of Physics, College of Science, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Department of Biophysics, Institute for Research & Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Elif Esra Altuner Sen Research Group, Department of Biochemistry, Dumlupinar University, Kutahya, Turkey Muthu Arumugam Microbial Processes and Technology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum, Kerala, India Academy of Scientific and Innovative Research (AcSIR), CSIR, Ghaziabad, India Naim Aslan School of Tunceli, Department of Mechanical and Metal Technologies, Munzur University, Tunceli, Turkey Munzur University Rare Earth Elements Application and Research Center, Tunceli, Turkey xix

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Contributors

Burhan Ates Biochemistry and Biomaterials Research Laboratory, Department of Chemistry, Faculty of Arts and Science, İnönü University, Malatya, Turkey Sonia Bahrani Health Policy Research Center, Health Institute, Shiraz University of Medica Sciences, Shiraz, Iran Felipe Fernandes Barbosa Laboratório de Peneiras Moleculares (LABPEMOL), Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil K. C. Barick Chemistry Division, Bhabha Atomic Research Centre, Mumbai, India Homi Bhabha National Institute, Mumbai, India A. Baykal Department of Nanomedicine Research, Institute for Research & Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Muhammed Bekmezci Sen Research Group, Department of Biochemistry, University of Dumlupinar, Kutahya, Turkey Department of Materials Science & Engineering, Faculty of Engineering, University of Dumlupinar, Evliya Celebi Campus, Kutahya, Turkey Pankaj Bharali Department of Chemical Sciences, Tezpur University, Tezpur, India Debasrita Bharatiya Department of Chemistry, Veer Surendra Sai University of Technology, Burla, Sambalpur, India Loukya Boddapati Nanostructured Materials Research Group, International Iberian Nanotechnology Laboratory, Braga, Portugal J. P. Borah Nanomagnetism Group, Department of Physics, National Institute of Technology Nagaland, Dimapur, Nagaland, India Biraj Jyoti Borah Department of Chemical Sciences, Tezpur University, Tezpur, India Tiago Pinheiro Braga Laboratório de Peneiras Moleculares (LABPEMOL), Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil Sibel Büyüktiryaki Yunus Emre Vocational School of Health Services, Department of Medical Services and Techniques, Anadolu University, Eskişehir, Turkey Nadia Chekalil Laboratoire de Synthèse Organique Appliquée (LSOA), Département de Chimie, Faculté des Sciences Exactes et Appliquées, University of Oran 1, Oran, Algeria Bhaskar J. Choudhury School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Guwahati, India

Contributors

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Mohammed Danish Bioresource Technology Section, School of Industrial Technology, Universiti Sains Malaysia, Penang, Pulau Pinang, Malaysia Tanveer Ahmad Dar Department of Physics, Islamic University of Science and Technology, Awantipora, India Pragnesh N. Dave Department of Chemistry, Sardar Patel University, Anand, Gujarat, India Francis Leonard Deepak Nanostructured Materials Research Group, International Iberian Nanotechnology Laboratory, Braga, Portugal Jianping Deng State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, China Gamze Dik Biochemistry and Biomaterials Research Laboratory, Department of Chemistry, Faculty of Arts and Science, İnönü University, Malatya, Turkey A. Dinesh Department of Chemistry, Government Arts College for Men (Autonomous), Nandanam, Chennai, Tamil Nadu, India M. Durka Department of Physics, Bharath Institute of Higher Education and Research (BIHER), Bharath University, Chennai, Tamil Nadu, India Bijaideep Dutta Chemistry Division, Bhabha Atomic Research Centre, Mumbai, India Homi Bhabha National Institute, Mumbai, India Mahsa Ebizadeh Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran Ahmed A. El-Gendy Department of Physics, University of Texas El Paso, El Paso, TX, USA Nursev Erdogan Turkish Aerospace, Advanced Material, Process and Energy Technology Center, Ankara, Turkey Arzu Ersöz Department of Chemistry, Eskişehir Technical University, Eskişehir, Turkey Yohannes W. Getahun Department of Physics, University of Texas El Paso, El Paso, TX, USA Navdeep Goyal Department of Physics, Panjab University, Chandigarh, India Vijayasri Gunasekaran PG Department of Physics, Vellalar College for Women (Autonomous), Erode, Tamilnadu, India Department of Physics, Mohamed Sathak Engineering College, Ramanathapuram, India

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Contributors

Nguyen Thi Nhat Hang Institute of Applied Technology, Thu Dau Mot University, Thu Dau Mot City, Binh Duong Province, Vietnam Essia Hannachi Department of Nuclear Medicine Research, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Seyyed Alireza Hashemi Nanomaterials and Polymer Nanocomposites Laboratory, School of Engineering, University of British Columbia, Kelowna, BC, Canada Department of Mechanical Engineering, Center for Nanofibers and Nanotechnology, National University of Singapore, Singapore, Singapore P. A. Hassan Chemistry Division, Bhabha Atomic Research Centre, Mumbai, India Homi Bhabha National Institute, Mumbai, India Krishna Priya Hazarika Nanomagnetism Group, Department of Physics, National Institute of Technology Nagaland, Dimapur, Nagaland, India Mohammad Irani Department of Pharmaceutics, Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran Riyajul Islam Nanomagnetism Group, Department of Physics, National Institute of Technology Nagaland, Dimapur, Nagaland, India Rüstem Keçili Yunus Emre Vocational School of Health Services, Department of Medical Services and Techniques, Anadolu University, Eskişehir, Turkey I. Khan Department of Chemistry, University of Glasgow, Glasgow, UK Ekta Khosla Department of Chemistry, RR Bawa DAV College for Girls, Batala, Punjab, India Mümin Mehmet Koç School of Medical Service, Department of Medical Service and Techniques, Kırklareli University, Kırklareli, Turkey T. Sujin Jeba Kumar Microbial Processes and Technology Division, National Institute for Interdisciplinary Science and Technology (NIIST), Council of Scientific and Industrial Research (CSIR), Trivandrum, Kerala, India Academy of Scientific and Innovative Research (AcSIR), CSIR, Ghaziabad, India Alice G. Leonel Center of Nanoscience, Nanotechnology and Innovation – CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais – UFMG, Belo Horizonte, MG, Brazil Pengpeng Li State Key Laboratory of Chemical Resource Engineering, College of Materials Science and Engineering, Beijing University of Chemical Technology, Beijing, China Nguyen Viet Long Institute of Applied Technology, Thu Dau Mot University, Thu Dau Mot City, Binh Duong Province, Vietnam

Contributors

xxiii

Nyemaga Masanje Malima Department of Chemistry, University of Zululand, KwaDlangezwa, KwaZulu-Natal, South Africa Department of Chemistry, College of Natural and Mathematical Sciences, University of Dodoma, Dodoma, Tanzania A. Manikandan Department of Chemistry, Bharath Institute of Higher Education and Research (BIHER), Bharath University, Chennai, Tamil Nadu, India Centre for Catalysis and Renewable Energy, Bharath Institute of Higher Education and Research (BIHER), Bharath University, Chennai, Tamil Nadu, India Nikolaos Maniotis Department of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece Alexandra A. P. Mansur Center of Nanoscience, Nanotechnology and Innovation – CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais – UFMG, Belo Horizonte, MG, Brazil Herman S. Mansur Center of Nanoscience, Nanotechnology and Innovation – CeNano2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais – UFMG, Belo Horizonte, MG, Brazil Maicon Oliveira Miranda Laboratório de Peneiras Moleculares (LABPEMOL), Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil Instituto Federal de Educação, Ciência e Tecnologia do Piauí (IFPI), Cocal, PI, Brazil Vijayanand S. Moholkar School of Energy Science and Engineering, Indian Institute of Technology Guwahati, Guwahati, India Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati, India Seyyed Mojtaba Mousavi Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan Mythili Narayanan Department of Physics, Krishnasamy College of Science, Arts and Management for Women, Cuddalore, Tamilnadu, India D. Navadeepthy Department of Nanoscience and Technology, Bharathiar University, Coimbatore, TN, India Masayuki Nogami Nagoya Institute of Technology, Showa, Nagoya, Japan Marjan Nouri Department of Food Science and Technology, Roudehen Branch, Islamic Azad University, Roudehen, Iran Johnatan de Oliveira Soares Laboratório de Peneiras Moleculares (LABPEMOL), Instituto de Química, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil

xxiv

Contributors

Shesan John Owonubi Department of Chemistry, University of Zululand, KwaDlangezwa, KwaZulu-Natal, South Africa Salih Ozbay Department of Chemical Engineering, Sivas University of Science and Technology, Sivas, Turkey Ebru Birlik Özkütük Department of Chemistry, Faculty of Science and Letters, Eskişehir Osmangazi University, Eskişehir, Turkey Biswajit Parhi Department of Chemistry, Veer Surendra Sai University of Technology, Burla, Sambalpur, India N. Ponpandian Department of Nanoscience and Technology, Bharathiar University, Coimbatore, TN, India Leila Roshanfekr Rad Faculty of Chemistry, Iran University of Science and Technology, Narmak, Tehran, Iran K. Kanmani Raja Department of Chemistry, Government Arts College for Men (Autonomous), Nandanam, Chennai, Tamil Nadu, India Gurusamy Rajagopal PG and Research Department of Chemistry, Chikkanna Government Arts College, Tiruppur, Tamilnadu, India Jegathalaprathaban Rajesh Department of Chemistry, Saveetha School of Engineering, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamilnadu, India Neerish Revaprasadu Department of Chemistry, University of Zululand, KwaDlangezwa, KwaZulu-Natal, South Africa Salima Saidi-Besbes Laboratoire de Synthèse Organique Appliquée (LSOA), Département de Chimie, Faculté des Sciences Exactes et Appliquées, University of Oran 1, Oran, Algeria Rıdvan Say Bionkit Co Ltd. Anadolu University Teknopark, Eskişehir, Turkey Fatih Sen Sen Research Group, Department of Biochemistry, Dumlupinar University, Kutahya, Turkey Ahmad Shafee Public Authority of Applied Education & Training, College of Technological Studies, Applied Science Department, Shuwaikh, Kuwait M. Sheikholeslami Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran Renewable Energy Systems and Nanofluid Applications in Heat Transfer Laboratory, Babol Noshirvani University of Technology, Babol, Iran Ginena Bildard Shombe Department of Chemistry, University of Zululand, KwaDlangezwa, KwaZulu-Natal, South Africa Chemistry Department, University of Dar es Salaam, Dar es Salaam, Tanzania

Contributors

xxv

Vineeta Shukla Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India Konstantinos Simeonidis Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki, Greece Rimmy Singh Department of Applied Science and Humanities, DPG Institute of Technology and Management, Gurugram, India Yassine Slimani Department of Biophysics, Institute for Research and Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Y. Slimani Department of Biophysics, Institute for Research & Medical Consultations (IRMC), Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia Chandan Srivastava Department of Materials Engineering, Indian Institute of Science, Bangalore, India G. Srividhya Department of Nanoscience and Technology, Bharathiar University, Coimbatore, TN, India Sarat Kumar Swain Department of Chemistry, Veer Surendra Sai University of Technology, Burla, Sambalpur, India Khadidja Taleb University of Oran 1, Laboratoire de Synthèse Organique Appliquée (LSOA), Département de Chimie, Faculté des Sciences Exactes et Appliquées, BP 1524 El Mnaouer, Oran, Algeria Faculté de médicine, University of Oran 1, Oran, Algeria K. Thanrasu Department of Chemistry, Government Arts College for Men (Autonomous), Nandanam, Chennai, Tamil Nadu, India Marco Antonio Morales Torres Departamento de Física, Universidade Federal do Rio Grande do Norte, Natal, RN, Brazil Ahmet Ulu Biochemistry and Biomaterials Research Laboratory, Department of Chemistry, Faculty of Arts and Science, İnönü University, Malatya, Turkey Anjana K. Vala Department of Life Sciences, Maharaja Krishnakumarsinhji Bhavnagar University, Bhavnagar, India K. C. Verma Materials Science & Sensor Applications (MSSA), CSIR-Central Scientific Instruments Organisation, Chandigarh, India Department of Physics, Panjab University, Chandigarh, India Trupti K. Vyas Food Quality Testing Laboratory, N M College of Agriculture, Navsari Agricultural University, Navsari, India Yong Yang State Key Laboratory of High-Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, China

Part I Theory, Modeling, and Synthesis

1

Nanotechnology and Medical Applications Mohammad Irani, Parvaneh Ghaderi-Shekhi Abadi, Leila Roshanfekr Rad, and Mahsa Ebizadeh

Contents Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials for Drug Delivery and Cancer Therapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gene Delivery-Based Nanomedicine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterial-Based Nanocarriers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Carbon Nanomaterials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Magnetic Nanoparticles for Delivery Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Metal Nanoparticles for Delivery Process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials in Tissue Engineering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Materials Used for Nanostructured Scaffolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Electrospun Scaffolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydrogel-Based Scaffolds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials Used for Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials for Detection of Pathogens . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials for Detection of Proteins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nanomaterials Used in Diagnostics and Therapy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 6 8 9 10 13 18 20 21 21 24 25 25 28 30

M. Irani (*) Department of Pharmaceutics, Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran e-mail: [email protected] P. G.-S. Abadi Environmental Health Engineering Research Center, Alborz University of Medical Sciences, Karaj, Iran Non-communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran e-mail: [email protected] L. R. Rad Faculty of Chemistry, Iran University of Science and Technology, Narmak, Tehran, Iran e-mail: [email protected] M. Ebizadeh Faculty of Pharmacy, Alborz University of Medical Sciences, Karaj, Iran e-mail: [email protected] © Springer Nature Switzerland AG 2022 S. Thomas, A. Rezazadeh Nochehdehi (eds.), Handbook of Magnetic Hybrid Nanoalloys and their Nanocomposites, https://doi.org/10.1007/978-3-030-90948-2_1

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Future of Nanomedicine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Abstract

Nanomedicine is a new field of science and technology in medicine science 1980. Nanomedicine is the use of nanotechnology in medicine for improving the diagnosis and therapy of diseases. In this chapter the applications of nanotechnology in medicine such as drug delivery, gene delivery, tissue engineering, protein detection, pathogen detection, and diagnosis detection have been reviewed for the treatment and monitoring of diseases. The potential of nanotechnology for the therapy of cancer and other diseases have been also discussed. Keywords

Nanomedicine · Drug delivery · Nanotechnology · Gene delivery · Diagnosis

Introduction Nanotechnology could be introduced as the developing, synthesizing, characterizing, and application of materials and devices by modifying their size and shape in nanoscale. Actually the word “nano” is derived from the Greek word nanos or Latin word nanus means which “dwarf.” The basic and the key elements of nanotechnology are the “nanomaterials.” The nanomaterials are the materials with less than 100 nm size ones at least in one dimension. Based on the dimensions of nanoscale (< 100 nm), they are classified as zero-dimensional, one-dimensional, two-dimensional, and three-dimensional produced from various organic materials such as polymers, liposomes, dendrimers, micelles, and inorganic materials such as gold, metal oxides, activated carbon, and their hybrids. The several methods could be used for the synthesis of nanomaterials such as biological, physical, and chemical methods. To synthesize the nanomaterial via the biological methods, the various bacteria, Actinomycetes, yeasts, fungi, viruses, plants, starches, β-D-glucoses, proteins peptides, amino acids, polysaccharides, citric acid, lipids, and nucleic acids have been utilized as safe, economically feasible, and ecofriendly agents. These agents can be acted as a capping and reducing agent in the synthesis of nanomaterials. A small number of previously papers focused on the synthesis of carbon nanomaterials via biological methods. But the metallic and magnetic nanomaterials have been widely synthesized via biological methods. Typically, the synthesis of Au and Fe3O4 nanomaterials via biological methods with various sizes are listed in Table 1. The physical method includes the laser evaporation, radiofrequency plasma, thermal decomposition methods, and mechanical milling. These methods have been carried out in liquid or gaseous phases. The nanomaterials synthesized by these method did not widely use in medical applications.

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5

Table 1 Synthesis of Au and magnetic nanomaterials by various biological agents and methods No. 1 2 3 4 5 6 7 8 9

Nanomaterial Au Au Au Au Au Au Au Au Au

10 11 12 13 14 15 16 17

Au Au Au Fe3O4 Fe3O4 Fe3O4 Fe3O4 Fe3O4

Biological agent Shewanella algae (bacteria) Xylotrophic (fungi) Aptamer/bovine serum albumin (protein) Escherichia coli (bacteria) Phomopsis sp. XP-8 (fungi) Ureibacillus thermosphaericus (bacteria) Yarrowia lipolytica (yeast) Escherichia coli (bacteria) Aspergillus flavus, Rhizoctonia solani, Fusarium oxysporum, and Verticillium dahliae (fungi) Staphylococcus aureus (bacteria) Xylanases (fungi) Neurospora crassa (fungi) Bacillus subtilis (bacteria) Pro-Glu (protein) Magnetospirillum magnetotacticum (MS-1) (bacteria) Shewanella oneidensis (bacteria) Yeast (yeast)

Size (nm) 1–10 5–25 1.77  0.51 20–30 – 50–70 15 10 20–40 51.11 6.98–52.51 32 67.28 5 50 40–50 80
C) and (b) magnetic fluid hyperthermia and equable temperatures (for noncovalent interaction between secondary phases, 40 until 45
C). In Table 2, some secondary-phase magnetic nanocarriers@drug systems including nanocarrier and drug conjugate with covalent and noncovalent bonds are listed. (1) Adriamycin and main chains of polymer cage were conjugated via acidresponsive linkers. The pour polymer showed no significant cytotoxicity against human hepatocellular carcinoma (HepG2) cells due to biocompatible poly(ethylene glycol) and poly(aspartate)-graft-dodecylamine. However, Adriamycin conjugate poly(aspartate)-graft-poly(ethylene glycol)-dodecylamine-hydrazone-iron oxide nanoparticles showed significant cytotoxicity against the HepG2 cells (80–95% of liver cancer cells remained viable after 4 h incubation) (Huang et al. 2013a). (2) DOX conjugate dextran-graft-poly(N-isopropyl acrylamide-co-N,N-dimethyl

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Fig. 6 Schematic of (a, c, f) magnetic polymers with hydrophilic and hydrophobic agents, (b) magneto-liposomes, (d) magneto-micelles, and (e) condensed clusters loading drug on carbon nanomaterials surface (Ulbrich et al. 2016)

acrylamide-Fe3O4-SCH2CH2CONHNH2) cage was obtained via coupling interaction between hydrazide groups of cage and carbonyl groups of DOX (absorption band in 1655 cm1 is attributed to appear C¼N bonds) (Zhang and Misra 2007). (3) The iron oxide via its amine groups was interacted with –COOH group of hyaluronan. Then, under 6 pH, the hydrazone linkage was formed between the carbonyl group of DOX and the hydrazide groups of iron oxide/hyaluronan. Under release condition (4.5 pH), the hydrazone linker was cleaved. Then, DOX was released from the drug formulation (El-Dakdouki et al. 2012). (4) Carboxymethyl dextran via –C  C groups were interacted with –N3 groups of SFSIIHTPILPL (targeting peptide SP94), and –CH2 groups of DOX were banded with –NH2 groups of dextran to fabricate Fe3O4-carboxymethyl dextran/SP94, DOX. 300 μg/mL of this drug formulation can captured and isolated 75% of the target HepG2 cells (cell viability nearly 23%) from a sample with 2  105 HepG2 cells in 1 mL DMEM after

DOX

DOX

Targeting peptide SP94, DOX Methotrexate

Ethosuximide

Carmustine

Cisplatin

Cytokine IFN-Ỵ

DNA

2

3

4

6

7

8

9

10

5

Drug Adriamycin

No. 1

PEI

Dimercaptosuccinic acid

Poly(acrylic acid)/polyvinyl alcohol

Poly(ethylene oxide)/poly(propylene oxide)/ poly(ethylene oxide)/polyvinyl alcohol Poly(propylene oxide)/polyacrylic acid

Auric acid

Carboxymethyl dextran

Secondary phase Poly(aspartate)-graft-poly(ethylene glycol)dodecylamine Dextran-graft-poly(N-isopropylacrylamide-coN,N-dimethylacrylamide Hyaluronan

80 nm

400 nm

186  13 nm

20–50 nm

Magnetic targeting release

Magnetic targeting release

Magnetic targeting/high-intensity focused ultrasound release Magnetic targeting release

Magnetic fluid hyperthermia release

Magnetic targeting release

24

3–4

Caproic acid

Glycolic acid

L-lactic acid

Polyglycolic acid PGA

12–18

Polylactic acid PLA

1.5–2.7

173–178

Polymers

60–65

Thermal and mechanical properties Degradation properties Glass transition Tensile temp. modulus Time Melting
(
C) (GPa) (month) Products tem. ( C)

Chloroform, hexafluoroisopropanol, dichloromethane, toluene

Hexafluoroisopropanol, acetone, dichloromethane, chloroform

Chloroform, dioxane, dichloromethane, ethyl acetate, acetone, tetrahydrofuran, hexafluoroisopropanol

Solvent

Processing and applications

Fracture fixation, interference screws, suture anchors, meniscus repair Suture anchors, meniscus repair, medical devices, drug delivery Suture coating, dental, orthopedic implants

Applications

Polymer repeat unit structure

Bendix (1998), Lepoittevin et al. (2002), Li et al. (2002), Kang et al. (2007)

Saracino et al. (2012), Shin et al. (2003), Koegler and Griffith (2004), Lu et al. (2000) Saracino et al. (2012), Shin et al. (2003), Lu et al. (2000)

Refs.

Table 3 Special properties of the biodegradable polymers scaffolds (Saracino et al. 2012; Shin et al. 2003; Koegler and Griffith 2004; Lu et al. 2000; Bendix 1998; Lepoittevin et al. 2002; Li et al. 2002; Kang et al. 2007; Shi et al. 2005)

22 M. Irani et al.

30–50

60

2–3

Depends on the formulation and composition several months >24

> 1, the growth is said to be controlled by the reaction, and for K 50 mrad). It can help in distinguishing the chemistry of an atomic column because the intensity of contrast in HAADF-STEM images is directly proportional to ~Z1.4 (Z: atomic number)

Fig. 2 Schematic diagram of HAADF-STEM and ABF-STEM techniques

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597

Pt Au

100

Intensity (AU)

80

60 Pd

Ag

Mo

40 Cu Zn Fe Co Ni

20

Co

S O Si B C

0 Element

Fig. 3 Profiles of intensity obtained from a series of HRSTEM-simulated images (at a defocus of 41 nm). Note the intensity variation with the different elements. In each case the columns of elements have the same number of atoms. (Reprinted with permission from Francis et al. (2014))

(Deepak et al. 2018). On the other hand, the ABF-STEM imaging technique utilizes the scattered electrons collected from the sample at relatively low collection angles, and it is very sensitive to light elements, even to the lightest element, hydrogen. The combination of the atomic-number sensitivity, light-element sensitivity, and high resolution makes STEM an extremely useful tool to the comprehensive study of clusters, alloy nanoparticles, interfaces, and grain boundaries/defects in all kinds of materials. As mentioned previously, HAADF-STEM imaging works remarkably well in the case of nanoalloys; the differences among different metals that make up the nanoalloy are evident due to the intensity dependence on atomic number, with minimum dependence on microscope defocus (Wall et al. 1974). This is definitely different from what is expected of bright field imaging, where the signal varies weakly and non-monotonically with Z. Figure 3a shows a Z-contrast STEM image simulation of single atoms of different elements, arranged in a 4
4 matrix (Francis et al. 2014). The line scan through the center of the atomic positions is shown at the right of the simulated image (Fig. 3b). The trend follows approximately a Z1.4 relation, very close to the dependence expected by Pennycook et al. (Pennycook and Boatner 1988; Pennycook and Jesson 1991).

Aberration-Corrected TEM/STEM One major goal of electron microscopy is to be able to acquire images that are directly interpretable and provide new important information about the materials under study. However, because of unavoidable imperfections in electromagnetic lenses, most conventional TEMs suffer from a variety of aberrations that diminish the obtainable resolution. A few of the major ones are spherical aberration, chromatic aberration, and astigmatism. The most severe is spherical aberration (Cs),

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which causes image delocalization, or an inability to define the specific location of a feature, where the image of a point is represented as a blurred disk. This is due to the inhomogeneous forces that the lens (objective for conventional TEM and condenser for STEM) transfers to off-axis electron beams, and the extent of blurring depends on both the magnitude of the spherical aberration coefficient (Cs) and the objective lens strength (Fig. 4). The smearing/delocalization limits the resolution of the TEM and the ability to interpret an image properly. To minimize the effects of delocalization, it is critical to image as close to the Scherzer defocus as possible. The Scherzer defocus defined in Eq. 1 is the optimal objective lens condition for a given microscope and limits the effect of delocalization: Δ f Sch ¼ 1:2ðCs λÞ1⁄ 2

ð1Þ

ΔfSch is the defocus value, Cs is the coefficient of spherical aberration, and λ is the wavelength of the incident electron beam. In the case of chromatic aberrations, the defocus spread due to chromatic aberration is given by Cc ¼ dE/Eo, where Cc is the chromatic-aberration coefficient of the lens, dE is the energy loss of the electrons, and Eo is the initial beam energy (Fig. 5).

Fig. 4 Spherical aberration caused by the lens field acting inhomogeneously on the off-axis rays

Fig. 5 Illustration of the main lens aberrations. (a) A perfect lens focuses a point source to a single image point. (b) Chromatic aberration causes rays with different energies (indicated by color) to be focused differently

a

No aberration

b

Real lens

a

No aberration

b

Real lens

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599

In order to overcome Cc and achieve an information limit better than (0.1 nm)1, TEMs are additionally equipped with a monochromator.

Spectroscopic Techniques In TEM, the most common spectroscopic techniques include energy dispersive X-ray spectroscopy and electron energy loss spectroscopy. These transform electron microscopy beyond imaging into a far more powerful microscopy, namely, analytical electron microscopy (Egerton 2011; Deepak and Casillas 2017; Jose-Yacaman et al. 2013).

Energy-Dispersive X-Ray Spectroscopy (EDX/XEDS) In this technique, the characteristic X-rays are generated when the electron beam strikes the specimen (Fig. 6a). These X-rays can be detected by a semiconductor detector and identified as to which characteristic elements they originated from. The X-ray counts as a function of the energy (in keV) form a spectrum, called X-ray energy-dispersive spectrum (Fig. 6b). EDX can be used to find the chemical composition of materials, analyze the abundance of specific elements, and show element composition distribution over a much broader raster area. However, in some cases, the energy peaks overlap among different elements, and hence the lightest elements cannot be detected, which sometimes limits the application of EDX. However, EDX can provide fundamental compositional information for a wide variety of materials, including small alloy nanoparticles. EDX in STEM mode can be used for mapping the composition of a region of interest. In this technique of spectrum imaging, a complete spectrum is collected at every pixel, and the various X-ray peaks could be used for obtaining chemical maps during post processing.

Electron Energy Loss Spectroscopy (EELS) When the electrons pass through the specimen, the transmitted electrons will lose a measurable amount of energy. These electrons as a function of the energy lost form a spectrum. This spectrum is referred to as EELS spectrum. Compared with EDX, EELS is particularly sensitive to lighter elements, and it is useful for thinner TEM samples. EELS is a more difficult technique but is a useful tool to measure the thickness of specimen, chemical bonding, electronic structure, and atomic composition. EELS involves the energy analysis of inelastically scattered electrons from a nearly monochromatic electron beam due to interaction with electron-transparent specimen. Typically, a magnetic prism disperses these electrons according to energy, subsequent to which a spectrometer located at the correct position can collect electrons of a specific energy (Williams and Carter 2009; Egerton 2011). Electron

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a

L La Ka Kb

K

Kicked-out electron

Atomic nucleus External stimulation

K L M

Radiation energy

Counts [a. u.]

b

0

5

10 Energy (keV)

15

20

Fig. 6 The schematic illustrates the process of X-ray emission in energy dispersive X-ray analysis (a) and a typical EDX spectrum (b)

energy loss occurs due to excitations of various internal energy modes – typically electronic (with ΔE in the UV-vis region) and vibrational (IR region) – in the nanoparticle (NP) or in molecular adsorbates on the specimen surface. For example, EELS can be used to measure surface plasmon spectra for nanoparticles and vibrational spectra of molecules adsorbed on nanoparticles. The high spatial resolution of EELS can be used to map out surface plasmons across a nanoparticle, which is particularly useful for alloy nanoparticles, where the composition may vary across the particle. High-resolution EELS (HREELS) is a variant of EELS with energy resolution in the 100 meV range. As in the case of EDX, spectrum imaging can be achieved using various features in EELS spectrum when EELS is carried out in the STEM mode.

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Magnetic Nanoalloys and Nanocomposites Magnetic Spinel Nanoparticles Magnetic nanoparticles and their related nanoalloys have become the subject of interest in key areas of research encompassing nanoscience and nanotechnology, due to their unique properties. The properties of these nanoparticles are mainly determined by their mean size distribution, shape, structure, and chemical composition. These characteristics are controlled during their synthesis so that they are suitable for specific applications. Iron oxide polymorph magnetite (Fe3O4) has a multidomain magnetic structure exhibiting high Curie temperature (840 K) and high saturation magnetization (98 emu/g). However, in the nanoparticle form, the magnetic behavior of Fe3O4 is predominantly dependent on the size of the nanoparticles. Ferrimagnetic (FiM) Fe3O4 undergoes transition from multi- to single-domain magnetic structure as the size is reduced to below 80–90 nm. Further reduction in their size to 25–30 nm induces superparamagnetic (SPM) state at room temperature. This transition from ferrimagnetic to superparamagnetic behavior is a result of the spontaneous flip of their magnetization (M) determined by the balance between the thermal energy and magnetic anisotropy. Such nanoparticles are particularly well suited for preparing colloidally stable dispersions, whereas larger (greater than 25–30 nm) aggregate under magnetic field due to the remanence and coercive forces. Colloidally stable SPM nanoparticles exhibit high saturation magnetization, good chemical stability, biocompatibility, and low toxicity, which therefore are suitable for diverse range of practical applications. They exhibit a wide variety of potential applications in magnetic recording media, spintronic devices, magnetic sensors, etc., and recently they are playing an active role in biotechnology research such as in cell sorting, drug delivery, optical coding, etc. (Wang et al. 2010; Kabir et al. 2010; Sun et al. 2000). Realizing specific applications for these nanoparticles requires synthesis of largesized (around 20 nm) nanoparticles with relatively narrow size distribution and elucidation of their structure as well as phase composition to determine the structure-property relationships. Large colloidal SPM Fe3O4 nanoparticles have been mainly prepared by (a) thermal decomposition (b) mild oxidation of Fe2+ precursor, and (c) coprecipitation followed by hydrothermal growth of particles. Other commonly followed synthesis methods for various magnetic nanoalloys that are continuously under investigation are arc-discharge, mechanical alloying, and hydrogen plasma-metal reaction (Djekoun et al. 2009). Although crystalline magnetic nanoalloys are readily available, they have the disadvantage of being prone to environmental degradation due to their high surface to volume ratio and reactivity (Sun et al. 2000). This limits their characterization and industrial application. In-depth characterization of the structure and phase composition of these nanoparticles is important, as the resultant properties are highly dependent on these parameters. In addition, understanding how the structure and phase composition depends on the synthesis method provides a precise control over their magnetic properties.

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Kolen’ko et al. (2014) have synthesized colloidal Fe3O4 nanoparticles in large quantities using improved methods based on controlled coprecipitation and hydrothermal synthesis (Kolen’ko et al. 2014). These particles are single-phase and devoid of any other impurity phases or distinct core-shell structures. The M vs H curves demonstrated SPM-like behavior with very high magnetization values. Based on high-resolution TEM, structural perfection observations, structural-defect-free nanoparticles, twinned nanoparticles, and “dimer” nanoparticles are observed. Geometric phase analysis is also performed on the HRTEM images for mapping the strain and to confirm the nature of such defects. The dimer and twinned nanoparticles are observed only in the hydrothermally synthesized particles which provide an insight into the mechanism of their formation. The influence of such defects on the resultant magnetic properties of the nanoparticles is not negligible. The high magnetization of these SPM nanoparticles approaching that of bulk magnetite (98 emu/g) is related to the large particle diameter (13–20 nm) and elevated temperature of the synthesis. Such high magnetization values provide a significant advantage, for example, in magnetic hyperthermia-related applications. These particles are also explored for nanoparticle-mediated magnetic hyperthermia performance, and the results are in good agreement with hyperthermia models that predict the correlation between heating ability and saturation magnetization. Generally, magnetic nanoparticles are considered to be single magnetic domains below a critical size, which is typically the order of domain wall width for the corresponding bulk material. Single-domain particles are expected to have maximum magnetic moment per volume which is desirable for their use in various applications. However, there are many reports on reduced magnetization relative to that of the bulk. Such reduction in the magnetization has been attributed to the variations in the crystallinity of the particles and to the surface spin disorder. However, reducing the surface roughness and increasing the crystallinity is not found to necessarily improve the magnetization. Nedelkoski et al. (2017) have demonstrated that even high-quality magnetite nanoparticles can have dramatic variations in their magnetic properties (Nedelkoski et al. 2017). High-resolution electron microscopy and atomic spin calculations are used to identify the origin of reduced magnetization and its anomalous temperature dependence. In this study, antiphase domain boundaries in nanoparticles are found to substantially reduce the magnetic moment in nanoparticles. Antiphase domain boundary defects are observed in substrate-supported thin film growth of magnetite and also in coreshell nanoparticles (Wetterskog et al. 2013; Margulies et al. 1997; Gilks et al. 2013). Strong antiferromagnetic super-exchange interactions across the antiphase domain boundaries are found to significantly reduce the magnetization of the nanoparticles due to the formation of multiple magnetic domains even in nanoparticles below 15 nm. Nedelkoski et al. (2017) have compared nanoparticles prepared by the groups of (Sun et al. 2004; Yu et al. 2004; Park et al. 2004) with well-established methods as having similar structure and chemical composition as confirmed by TEM techniques. However, the magnetic properties of these three particles are very different. Nanoparticles by Sun et al. (2004) are close to bulk magnetization, while those by Park

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et al. 2004 and Yu et al. 2004 showed less than half of the bulk-specific magnetization. Figure 7 shows the STEM-HAADF images of the nanoparticles: Fig. 7a Sun et al. (2004), Fig. 7 Yu et al. 2004, and Fig. 7c Park et al. 2004. The structural defects in the particles are indicated by dashed lines in Fig. 7b, c. Figure 7d shows the magnified view of the dashed area in (c) emphasizing the structural defect region. The anomalous magnetic behavior is correlated with the presence or absence of antiphase domain boundaries in the nanoparticles. For applications where the amount of magnetization is critical and the applied fields are low, it is preferable to have nanoparticles with low density of antiphase domain boundaries. Zero field cooled (ZFC) magnetization measurements are a convenient way to screen and

Fig. 7 HAADF-STEM images of representative iron oxide nanoparticles with diameters between 12 and 14 nm synthesized by three different known methods. (a) Nanoparticles from Ref. (Sun et al. 2004) viewed along [111] zone axis. (b) Nanoparticles from Ref. (Yu et al. 2004) viewed along [114] zone axis. (c) Nanoparticles from Ref. (Park et al. 2004) viewed along [11-2] zone axis. Structural defects are indicated with dashed lines in (b) and (c). (d) Magnified view of dashed area from (c) with a structural model in colored dots emphasizing the defect region. (Reprinted with permission from Nedelkoski et al. (2017))

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optimize the preparation methods to synthesize nanoparticles with minimum defects that reduce the magnetization. Magnetite, Fe3O4, with an inverse-spinel crystal structure is of AB2O4 type, (Fe3+)A[Fe2+Fe3+]BO4. Bulk Fe3O4 crystallizes in cubic space group, Fd-3 m. “A” sites are tetrahedrally coordinated by O atoms and are occupied by Fe3+ cations, while “B” sites are octahedrally coordinated by O atoms and are occupied by Fe2+ and Fe3+ atoms. Local structural distortions due to charge ordering of Fe2+ and Fe3+ was proposed by Verwey in 1939 and was recently validated by (Senn et al. 2012). Fe3O4 is known to exhibit finite size effect, where the magnetic properties of the bulk are different from its nanosized counterpart. As a result, bulk multidomain ferrimagnet (FiM) is transformed into a single-domain FiM on reducing the particle size to 80 nm, and further reduction in the size to 25 nm transforms it into a superparamagnet. The SPM magnetite nanoparticles usually exhibit high saturation magnetization (Ms) and high Curie Temperature (Tc). The magnetic and structural properties of Fe3O4 can be tuned by varying the particle size as well as by chemical doping. Intrinsic magnetic properties can be affected by elemental substitution in both tetrahedral and octahedral sites in the AB2O4 type structure. Transition metal doping studies in Fe3O4 have shown that Mn+2 has a tendency to replace Fe3+ in tetrahedral sites, while Co2+ and Ni2+ tend to replace Fe3+/Fe2+ in the octahedral sites. Doping in thin film and bulk Fe3O4 are primarily investigated, and they typically affect the structural, magnetic, and transport properties, whereas very little is known about such effects of doping in colloidal nanoparticles. Therefore, in-depth understanding of the changes in both structural and magnetic properties as a function of transition metal doping is of high interest from both technological and fundamental points of view. Synthesis of nanoparticles with effective dopant concentration in the structure is nontrivial due to thermodynamic reasons. Nanoparticles have thermodynamic preference that tends to expel dopants from the crystal structure in order to minimize the overall free energy, which is known as self-purification phenomenon (Erwin et al. 2005). In addition to this, compositionally complex nanoparticles tend to exhibit phase separation resulting in formation of secondary phases, which are also more favorable from a thermodynamic point of view. Solution-based synthesis methods developed for synthesis of colloidal nanoparticles largely rely on kinetic factors and so are not favorable to incorporate dopants into the nanoparticle crystal structure due to the thermodynamic issues as mentioned. Thermal decomposition approach has proved to be most effective and successful for synthesis of doped colloidal Fe3O4 nanoparticles. This technique, however, is not convenient due to the utilization of flammable organic solvents at high temperatures and is also restricted by low yields. Therefore, a robust method for synthesis of high-quality doped colloidal nanoparticles is necessary. Deepak et al. (2015a, b) reported MnxFe3-xO4 (M ¼ Mn, Co, Ni; x ¼ 0–1) colloidal nanoparticles synthesized with the low-temperature hydrothermal synthesis method (Kolen’ko et al. 2014; Deepak et al. 2015b). The preparation is realized in aqueous medium avoiding high-temperature syntheses using organic solvents. In this process, doped and non-doped nanoparticles are found to be single phased with average particle diameter between 7 and 12 nm. Detailed characterization of the

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nanoparticles showed interstitial substitution of Fe cations by the dopants with compositional uniformity. The magnetic characterization of as-synthesized nanoparticles as a function of dopant concentration showed a transformation from superparamagnetic to FiM with increasing Co concentration in CoxFe3-xO4 nanoparticles at room temperature. Transmission electron microscopy studies confirmed the inverse-spinel structure. No additional spots associated to any secondary phases are identified. HAADF-STEM images and the corresponding bright field STEM image of Ni0.15Fe2.85O4 are shown in Fig. 8. HAADF-STEM images in Fig. 8a,b shows brighter contrast for the Fe/Ni cation atomic positions and a weak contrast for the O positions. The bright field image in Fig. 8c clearly shows the oxygen environment around the Fe/Ni atoms. Intensity profile along a column of atoms is shown in Fig. 8d revealing the variation of intensities of Fe/Ni and O atomic columns. STEM-EDX and STEM-EELS elemental maps are obtained in order to confirm the elemental distribution of MxFe3-xO4 nanoparticles with different levels of doping. Figure 9 shows the STEM-EELS elemental maps of Ni0.6Fe2.4O4 nanoparticles which reveal uniform distribution of Fe and O atoms and random distribution of Ni without clustering or formation of any phase-separated particles. STEM-EDX line scan on individual representative nanoparticle of Ni0.6Fe2.4O4 showed decrease of Fe signal and a corresponding increase in Ni signal demonstrating the substitutional doping of Ni atoms in the nanoparticle. This study revealed a direct correlation between the magnetic properties and chemical composition of the MxFe3-xO4 nanoparticles. Mn and Ni doping leads to a significant decrease in the saturation magnetization, while the room temperature saturation magnetization of Co-doped samples is almost similar or slightly lower compared to that of the non-doped Fe3O4. It is also found that magnetite nanoparticles show ferrimagnetic behavior with Co doping, whereas they remain superparamagnetic with Mn and Ni doping. Low-dimensional morphologies of nanoparticles not only decrease the necessity of controlled manufacturing processes but also increase the degrees of freedom of material’s functionality. In functional materials, interplay of structure-property is strongly interlinked with the material’s functionality. The necessity to develop permanent magnetic materials for energy-related applications with rare earth elements-free (REE-free) elements is ever-increasing. In this regard, cobalt ferrite (CoFe2O4) with considerable saturation magnetization (400 emu/cm3) as well as magnetocrystalline anisotropy is of high interest in developing low-cost permanent magnetic materials for energy-conversion applications. Recently, several technical routes are reported for the preparation of CoFe2O4 nanomaterials, such as sol-gel method, hydrothermal method, co-precipitation, and solvothermal decomposition. Moreover, structure-controlled magnetism variations are widely reported in CoFe2O4 nanomaterials for targeted material design applications. For example, in CoFe2O4-based core/shell nanoparticles synthesized by Cannas et al. (2010), it is found that changed dipolar interparticle interactions resulting from the structure influence the magnetic behavior of the particles (Cannas et al. 2010). Fabrication of ordered arrays of monodisperse CoFe2O4 nanocrystals with tunable spherical and cubic shapes by highly controllable synthesis technique directly determines the magnetization behaviors of the particles (Bao et al.

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Fig. 8 (a, b) High-resolution HAADF-STEM images of Ni0.15Fe2.85O4 nanoparticles along [110] zone axis. The corresponding FFT pattern is shown in the inset. (c) Bright field (BF) STEM image. (d) Intensity profile along the line of atomic column indicating the intensity variation due to the difference in the atomic number between Fe/Ni (large peaks) and O (smaller peaks) as indicated by arrows. (Reprinted with permission from Deepak et al. (2015b))

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Fig. 9 (a) EELS spectrum showing the O K-edge, Fe L2,3-edges, and the Ni L2,3-edges from Ni0.6Fe2.4O4 nanoparticles. Elemental maps of (b) O K-edge, (c) Fe L2,3-edges, and (d) Ni L2,3edges demonstrating the uniform distribution of O and Fe and random distribution of Ni inside the nanoparticle. (Reprinted with permission from Deepak et al. (2015b))

2008). Wang et al. (2022) reported an efficient and highly feasible synthesis strategy for the fabrication of in-line spherical CoFe2O4 nanophase with necklace-like uniform structures (Wang et al. 2022). The temperature-dependent magnetism that originates from the microstructure and morphology are discussed which reveal the structureproperty interplays. The nanochain-like fibers are prepared by thermal decomposition using metalbased precursor solution and electrospinning method. The prepared electrospun polyacrylonitrile nanofibers are first stabilized at 573 K for 2 hours in air and then carbonized at various temperatures up to 1273 K for 2 hours. The magnetic hysteresis measurements show that the squareness of the hysteresis loops is improved with the increase in the carbonized temperature. This is due to the residual impurity originating from the organic solvents and supporting polyacrylonitrile fibers. The microstructure which is dependent on the carbonization temperature shows the evolution of necklace-like particles generation. Figure 10a and b show the HAADF-STEM images of the necklace-like CoFe2O4 particles. Figure 10b is

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Fig. 10 HAADF-STEM images of the chain-like CoFe2O4 nanostructures at (a) low-magnification and (b) representative nanochain-like structure of CoFe2O4 showing the interface between the nanocrystals

showing the inter-linked CoFe2O4 particles forming a necklace-like pattern. A closer look into the two particle interface clearly indicates the formation of grain boundaries and lattice distortion at the grain boundaries. Figure 11a shows the HAADFSTEM image of two particles with grain-boundary formation at the interface. The two crystals are found to be pure-phased single crystalline particles without forming any secondary phases as shown the fast Fourier transformed (FFT) patterns in the inset of Fig. 11a. The grain-boundary marked with yellow dotted square in Fig. 11a is magnified and shown in Fig. 11b. The high magnification image shows the CoFe2O4 atomic arrangement and lattice distortion at the grain boundary. Generally, magnetic properties tend to be suppressed by the presence of unavoidable magnetically inactive surface layer. However, high-temperature synthesis methods involving capping with organic acid results in excellent magnetic properties. The magnetization values through such synthesis are nearly as high as its bulk counterpart. The capping layer molecules are not magnetic, and so the origin of such enhanced magnetization is elusive. In order to understand the origin of such enhanced magnetism, it is necessary to characterize individual particle in real-space at subnanometer scales and probe the magnetic, chemical, and structural properties. Salafranca et al. (2012) mapped the magnetization of nanoparticles in real space with subnanometer spatial resolution using a STEM probe by electron magnetic circular dichroism (EMCD) technique (Salafranca et al. 2012; Schattschneider et al. 2006; Negi et al. 2015). The authors establish how the magnetization is restored in the surface layer by combining the experimental results with density functional theory (DFT)-based calculations. Magnetite nanoparticles are synthesized at high temperature with oleic acid as a surfactant. The saturation magnetization is ~80% of the bulk. The synthesized particles with sizes from 6 to 15 nm are characterized for crystal structure, magnetism, and spectroscopy by aberration-corrected STEM. Real-space magnetic

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Fig. 11 High magnification HAADF-STEM images of chain-like CoFe2O4 nanocrystals (a) at the interface showing the defect structure across the interface. The two nanocrystals are oriented along [110] zone axis. Fast Fourier transformed (FFT) images (i) from the left crystal (ii) at the interface and (iii) from the right crystal are shown in the inset. High magnification image of the defect structure from the region marked in yellow dotted square is shown in (b)

characterization of such small particles with subnanometer spatial resolution is possible by the aberration-corrected state-of-the-art techniques in TEM. EMCD is similar to the X-ray magnetic circular dichroism (XMCD) technique and utilizes L2,3 EELS absorption edges of transition metal elements to probe the local magnetization at room temperature. Thus, in this work, Salafranca et al. (2012) show for the first time how an EMCD signal can be obtained with a nanometer-sized electron probe (~ 1 nm in diameter) operating in nanodiffraction mode. Figure 12a shows a STEM bright field image of a highly crystalline nanoparticle (13 nm in size). High-quality crystal structure is maintained all the way to the surface even for the smallest particles as shown in Fig. 12b, c. I+ L2,3 and I L2,3 ratio maps obtained from the spectrum image of the nanoparticle in Fig. 12a are shown in Fig. 12d. Local magnetic moment is given by the difference in the L2,3 edges obtained from symmetrically conjugated spots in the nanodiffraction diagram as shown in Fig. 12e. The difference in L2,3 ratio profiles shown in Fig. 12f along the blue arrow direction on the nanoparticle in Fig. 12d indicates that the magnetic moment within 1 nm of the particle surface is at most 30% smaller than the magnetization of the core. This finding shows that the highly magnetic surface is contributing to the high saturation magnetization of these nanoparticles. The stabilization of such unexpectedly high surface magnetization in these high-quality crystalline nanoparticles at room temperature is interesting to study. This is addressed by aberration-corrected STEM-EELS experiments and by correlating the results with DFT-based theoretical calculations. The results show that functionalization processes that build onto the organic capping layer are expected to preserve the magnetism better than the functionalization processes based on ligand exchange. The resultant bond between organic acid and the nanoparticles prevents further oxidation to Fe2O3 which could be detrimental for magnetization. Further, O-Fe atomic configuration is restored with distances close to bulk values. This bulk-like surface structure is resulting in

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Fig. 12 (a) STEM image of Fe3O4 nanoparticle, (b, c) STEM image of Fe3O4 along [111] and [0–11] zone axes, respectively. (d) I+ L2,3 (left) and I L2,3 (right) ratio maps obtained from the spectrum image of nanoparticle shown in (a). (e) Fe L2,3 edges after background subtraction measured at I+ and I and the resultant difference spectra which is the dichroic signal (shown in blue and magnified by a factor of 5). (f) L2,3 profile along the blue arrow direction on the nanoparticle in (d). I+ and I L2,3 ratio maps are shown in red and black, respectively. The difference between I+ and I L2,3 ratios along the nanoparticle is shown in blue. Scale bar is 5 nm in all panels. (Reprinted with permission from Salafranca et al. (2012))

magnetization being restored in the surface layer and thus has a strong effect on the magnetic state of the nanoparticles.

Nanoalloys and Core-Shell Magnetic Nanoparticles Nanoalloys are metal nanoparticles composed of two or more metals that have unique electrical, optical, magnetic, and catalytic properties. MPt nanoparticles with M ¼ Mn, Fe, Co, Ni, or Cu have attracted much attention recently due to their strong ferromagnetic and electrochemical properties. By combining different metals, it is possible to tune the properties of the resulting nanoparticles. For example, bimetallic nanoparticles constitute promising catalysts in heterogeneous catalysis. Metals such as Co when alloyed with nonmagnetic materials such as Pt

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introduce catalytic effect into the final product. Catalytic and magnetic properties can be tuned in Co/Pt systems, whereas optical properties can be tuned in Au/Co nanoparticles. FePd alloy nanoparticles with high magnetocrystalline anisotropy energy (MAE) and Ms are suitable for ultrahigh-density magnetic storage applications. Bimetallic nanoparticles are most commonly produced using chemical procedures which usually result in core-shell structures with icosahedral or cuboctahedral geometries. However, the particles also form decahedra or truncated octahedral shapes. In the case of specific applications where the size and the shape of the particles is critical, physical methods are the best choice as they allow better control over these properties. Atomistic scale analysis of small bimetallic nanoparticles is challenging. With the development of aberration-corrected STEM combined with HAADF imaging, where the intensity is roughly proportional to Z2, it is possible to image the elements in the alloy based on their difference in the atomic weight. Mayoral et al. (2010) have performed an atomic analysis on the interface of bimetallic Au/Co nanoparticles, synthesized by sputtering technique where the particles are nucleated in the presence of a coolant inert gas (Mayoral et al. 2010). The particles are also subjected to thermal treatment where the particles are heated at 275  C for 12 hours and finally quenched to room temperature in a furnace. The STEM analysis of the nanoparticles (~ 5 nm in size) before thermal treatment revealed the formation of core-shell and bimetallic nanoparticles with frequent agglomeration into larger crystals due to high deposition times. The agglomeration of two particles occurred by the coalescence of two particles by forming a bimetallic nanoparticle with one side rich in Au and the other rich in Co. Alternately, particles can be rearranged into core-shell structure with Au core and cobalt oxide on the surface. Low magnification STEM imaging on the thermally treated particles did not reveal any significant changes in the particles after the process. In contrast, high-resolution STEM imaging revealed that the Co nanoparticles had rearranged their morphology to form a thin layer of ordered crystal structure with the Au nanoparticle at the core. In this study, atomic-scale STEM imaging of individual nanoparticles revealed its crystallinity, crystal structure, formation of atomic vacancies, and atomic rearrangement in bimetallic and core-shell structures. Thermal decomposition of Fe(CO)5 and reduction of Pt(acac)2 (acac ¼ acetylacetonate) are commonly used methods for preparing monodisperse FePt nanoparticles with controlled Fe/Pt compositions. This method for preparing CoPt nanoparticles via decomposition of Co2(CO)8 and reduction of Pt(acac)2 produces only Pt-rich CoPt nanoparticles, while the same is true for the synthesis of MnPt via decomposition of Mn2(CO)10 and reduction of Pt(acac)2. In other types of MPt with Ni or Cu, carbonyls are not readily available. Given the sensitivity of MPt magnetism and catalysis over M/Pt compositions, it is important to have a generalized synthetic process for each kind of MPt nanoparticle with a better control over the magnetic and catalytic properties. Yu et al. (2014) report a facile, yet general, synthesis method of monodisperse MPt (M ¼ Fe, Co, Ni, Cu, Zn) alloy nanoparticles via oleylamine (OAm) reduction of M(acac)2 and Pt(acac)2 (Yu et al. 2014). OAm is a primary amine with boiling point around 350  C and is widely used in solution phase synthesis of nanoparticles. In this study, the unique feature of the synthesis

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technique is that OAm serves as the solvent, surfactant, and reducing agent. The desired MPt nanoparticles are prepared by reacting M(acac)2 and Pt(acac)2 in OAm at 300  C. M/Pt compositions are controlled by the molar ratios of M(acac)2/Pt (acac)2. The TEM image of Co47Pt53 particles is shown in Fig. 13a, and HRTEM image of a representative Co47Pt53 particle is shown in Fig. 13b. The lattice fringe space measured from the HRTEM image confirms the face-centered cubic (fcc) CoPt alloy structure. In order to further characterize the alloy structure, HAADF imaging and STEM-EDS mapping of representative Co47Pt53 particle is performed. Figure 13c-g confirms the uniform distribution of Co and Pt within each nanoparticle which is also further confirmed by linear scan EDS across the Co47Pt53 particle (Fig. 13h). The HRTEM and HAADF-STEM along with STEM-EDS characterization of these nanoparticles confirm that OAm facilitate the nucleation and growth of CoPt into a solid solution structure. Transition metal (M) stabilization in MPt alloys under acidic conditions is challenging and crucial in order to boost Pt catalysis for oxygen reduction reactions (ORR). Pt in the nanostructured form is the key component in proton exchange membrane fuel cells (PEMFCs). It is important to minimize the use of Pt in largescale production of PEMFCs as Pt is not abundant in nature. Therefore, exploring the methods to improve Pt catalytic activity and stability is highly desirable. Recently, one of the common approaches explored is to alloy Pt with transition metal (M) to form nanostructured PtNi, Mo-doped Pt3Ni, core/shell structured PtPb/Pt, and Pt3Co/Pt. MPt alloys are commonly prepared in cubic fcc type solid solution structures which have limited ability to stabilize M under acidic ORR conditions. As a result, the effectiveness of M in Pt catalytic activity and stabilization is minimized in MPt nanostructures.

Fig. 13 (a) Transmission electron microscopy image of Co47Pt53 nanoparticles. (b) HRTEM image of nanoparticles shown in (a). (c) HAADF image of Co47Pt53 nanoparticles. Elemental mappings of (d) Co signal (red), (e) Pt signal (green), (f) Co (red)/Pt (green) combined. (g) Combined HAADF and the corresponding elemental mapping of Co47Pt53 particles. (h) EDS line scan across Co47Pt53 nanoparticles with inset showing the scanned particle. (Reprinted with permission from Yu et al. (2014))

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Recently, intermetallic L10-structured FePt has attracted much attention in stabilizing M in MPt alloy against uncontrolled leaching of M under acidic conditions. Unlike cubic intermetallic L12-MPt3 nanoparticles, tetragonal L10-FePt with Fe:Pt in 1:1 ratio and exhibiting strong magnetic character stabilize Fe efficiently against acid etching. Li et al. (2018a, b) reported on the synthesis and characterization of intermetallic and strongly ferromagnetic L10-CoPt/Pt nanoparticles with few atomic layers of Pt shell as an active ORR catalyst for fuel cell applications (Li et al. 2018b). STEM imaging played a key role in visualizing the core/shell structure of L10-CoPt/ Pt nanoparticle by identifying the Pt and Co atomic layers. Figure 14a show the

Fig. 14 (a) STEM image of L10-CoPt/Pt nanoparticles along zone axis direction. L10CoPt is the core with 2–3 atomic layers of Pt shell. (b) Schematic of L10-CoPt/Pt nanoparticles with Pt shell. Silver-colored atom is Pt and blue-colored atom is Co. (c) and (d) are the enlarged sections indicated by dashed squared in (a). Enlarged section of top dashed squared region is shown in (c) and bottom square is shown in (d). Yellow arrows indicate 2–3 layers of Pt shell. L10-CoPt/Pt core is shown (Pt colored in red and Co colored in blue), and d(111) spacing is marked. (Reprinted with permission from Li et al. (2018b))

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STEM images of core/shell L10-CoPt/Pt structure with the alternating layers of Pt and Co at the core and 2–3 atomic thick layers of Pt as the shell. Figure 14b is the schematic diagram of the L10-CoPt/Pt nanoparticle with 2–3 layers of Pt shell. Highmagnification STEM images in Fig. 14c, d clearly show the 2–3 atomic layers of Pt shell with the L10-CoPt/Pt core where Pt is colored in red and Co is colored in blue. FePd alloy nanoparticles with L10-type structural ordering is one of the materials for ultrahigh-density magnetic storage applications. L10 FePd alloy has a high magnetocrystalline anisotropy energy (MAE) as high as 1.7
106 J/m3 and a high saturation magnetization. FePd alloy nanoparticles similar to FePt can be synthesized by chemical solution methods or by physical vapor deposition. As-prepared nanoparticles are either nanocomposites of Fe and Pd (Pt) or disordered solid solutions with low magnetocrystalline anisotropy energies. In order to form L10 phase, high-temperature annealing is required. However, high degree of long-range order (LRO) in small nanoparticles is difficult to achieve via annealing. Sizedependent decay in LRO parameter is also observed in L10-FePd nanoparticles (Sato and Hirotsu 2005). Reduction in the coercivity is also possible in conjunction with the LRO decay in FePd nanoparticles. Sato et al. (2009) have reported on the intermetallic ordering and the nature of the reduced LRO in FePd nanoparticles. The structural characterization of the FePd alloy nanoparticles is studied using aberration-corrected HAADF-STEM imaging. Formation of epitaxial islands and the Fe-Pd alloying process deposited on a NaCl substrate is characterized by in situ reflection high-energy electron diffraction (RHEED) during deposition and the postdeposition annealing. Figure 15 is showing the HAADF-STEM imaging results. The sizes of the nanoparticles are Fig. 15 (a) 4 nm, (b) 6 nm, (c) 8 nm, (d) 9 nm, and (e) 11 nm. Partial formation of L12 phase at the center of the nanoparticle as indicated in Fig. 15a is observed. Therefore, local chemical orders in FePd nanoparticles with both the L10- and L12-type ordered phases are detected.

Carbon-Based Magnetic Nanocomposites Carbon Nanofiber-Based Nanocomposites Rare-earth-free (REF) permanent magnets have gained research interest in the past decade owing to their cost effectiveness, abundance, and promising magnetic properties. Researchers are continuously in search of materials to fill in the gap between most cost-effective but low-performing hard ferrite magnet and the most expensive but high-performing rare-earth element-based permanent magnets (Mohapatra and Liu 2018). Carbon-based nanostructures are promising due to their high conductivity, strength, and surface area. Carbon nanofibers (CNFs) have been essential in a wide-range of fields, such as aerospace, military, automotive, etc., due to their high mechanical strength and modulus, light weight, high chemical resistance and low thermal expansion. There are various approaches to fabricate CNFs such as arc discharge, laser ablation, chemical vapor deposition, etc. These methods require expensive equipment and operation and yet are relatively low-yield in production. Electrospinning is an efficient and cost-effective method to synthesize and assemble

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Fig. 15 HAADF-STEM Z-contrast images of FePd nanoparticles after annealing at 835 K for 10 min. Size of the nanoparticle and beam incidence directions in each image are as follows (a) 4 nm and [001]L12, (b) 6 nm and [001] L12, (c) 8 nm and [001]L10 þ [100]L10, (d) 9 nm and [001] L10, and (e) 11 nm and [001]L10 þ [001] L12. Corresponding Fourier spectra in the inset distinguish the L10- or L12-type ordering. Regions with chemically ordered structures showed uniform Z-contrast. The high magnification images in the inset from the regions with different image contrast. (Reprinted with permission from Sato et al. (2009))

ferromagnetic metal nanofibers. This is a simple and effective method for fabricating ultrathin nanofibers either oriented or laid as a random fibrous mat. The most used polymer precursor is polyacrylonitrile (PAN) since it is flexible to tailor the polymeric molecular structure. PAN also has high carbon fiber yield and easily forms the stabilized fibers via nitrile polymerization. The CNF can be obtained from the synthesized electrospun polymer nanofibers through heat treatment involving oxidative stabilization process followed by carbonization (Tang et al. 2020). Electrospinning method combined with heat treatment can result in ferromagnetic metal

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nanoparticle CNFs with interesting magnetic properties, but the conditions selected in the heat treatment process can be critical to the final production and the resultant yield. Helena et al. (2022) aimed to test the effect of a set of temperatures and atmospheric conditions in metallic nanoparticle CNF synthesis (Vaz et al. 2022). Ferromagnetic nanofibers containing Fe and Co nanoparticles are synthesized by preparing PAN solutions. Fe and Co precursors are selected and added into separate polymeric solutions which were then electrospun into nanofiber matts. These are then treated at different temperature cycles for stabilization and reduction of polymer and precursors before finally obtaining the carbon nanofiber-metal nanoparticle composites. The resulting nanofibers are characterized by scanning electron microscopy SEM and STEM-HAADF imaging. The samples prepared using the precursors, Fe acetylacetonate (2.5 wt.%) and Fe acetylacetonate (5 wt.%), are labeled as CNF-Fe1 and CNF-Fe2, respectively. Similarly, the samples prepared using the precursors, Co acetylacetonate (2.5 wt.%) and Co acetylacetonate (5 wt.%), are labeled as CNF-Co1 and CNF-Co2, respectively. As shown in Fig. 16a-d, SEM imaging of CNF-Fe1 and CNF-Fe2 revealed a mesh of well-defined nanofibers containing nanoparticles spread throughout the surface. Average sizes of CNF-Fe1 and CNF-Fe2 are around 29747 nm and 31153 nm. STEM-EDX mapping of CNF-Fe2 indicated the presence of carbon-based fibers with Fe agglomerates spread throughout the fiber. This confirms the successful synthesis of nanocomposites with nanoparticles embedded on carbon nanofibers. Similarly, as shown in Fig. 17a, b and Fig. 17c,d, SEM imaging of CNF-Co1 and CNF-Co2 revealed the formation of fiber mesh. The average sizes of CNF-Co1 and CNF-Co2 are 37554 nm and 537134 nm, respectively. STEM-EDX mapping of CNF-Co2 nanofibers revealed the presence of Co metal on their surface and in the interior appearing in clusters confirming the well-defined nanoparticles in the fibers. HRTEM imaging showed that the nanoparticles are not only attached on the surface of the nanofibers but are also well inserted inside the nanofiber. The size of the metal nanoparticle agglomerations are found to vary with metal concentrations in the fibers. Interestingly, lower concentration fibers showed larger metal nanoparticle agglomerates, while higher concentration fibers showed smaller metal nanoparticle agglomerates. This suggests that the concentration of the metal in the fibers could play a key role in determining the size of the metal agglomerates and thereby the resultant properties of the nanocomposites.

Magnetic-Graphene Nanoparticles There are several methods developed for controlled synthesis of magnetic metal or alloy nanoparticles. The resulting mean size of the particles, size distribution, and crystalline structure determine the properties of the nanoparticles. Although these magnetic metal or alloy nanoparticles are readily available, they are often prone to rapid environmental degradation due to their high surface to volume ratio and reactivity. This not only hinders the property characterization of these nanoparticles but also the use of these nanoparticles in industrial applications. A possible approach to solve this is to cover the magnetic metallic nanoparticles with nonmagnetic coating

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Fig. 16 SEM imaging of carbon nanofibers. (a, b) CNF-Fe1 and (c, d) CNF-Fe2 at low and high magnifications, respectively, in each case. (e) STEM imaging of CNF-Fe2 nanofiber and (f) respective STEM-EDX carbon mapping and (g) Fe mapping

thereby controlling the magnetic interactions and creating core/shell nanostructures. In comparison to polymer and silica shells which are widely studied, carbon coatings exhibit higher stability in chemical and physical environments. On the other hand, the importance of smart polymers in a wide range of applications such as biomedical, coatings, and microelectronics is increasing. Intelligent devices operated by electric and magnetic fields unlike those operated by diffusion processes have shorter responsive times. One of the appealing solutions for the preparation of highly efficient magneto-responsive materials requires filling of polymer materials with magnetic nanoparticles. Fe-, Co-, and Ni-based alloys show excellent magnetic properties, such as very high magnetization, low coercive forces, low magnetostriction, etc.,

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Fig. 17 SEM imaging of carbon nanofibers. (a, b) CNF-Co1 and (c, d) CNF-Co2 at low and high magnifications, respectively, in each case. (e) STEM imaging of CNF-Co2 nanofiber and (f) respective STEM-EDX carbon mapping and (g) Co mapping

required in soft magnetic materials for applications, such as transformers, inductive devices, etc. In particular FeCo-alloy nanoparticles are interesting due to their superior magnetic properties such as high saturation magnetization, high Curie temperature, low coercivity, low magnetocrystalline anisotropy, etc. Specifically, FeCo-alloy-based nanoparticles are prepared by a wide variety of techniques such as thermal decomposition, reductive decomposition of organometallic precursors, polyol-assisted processes, etc. Some applications also require operation at high temperatures while preserving the alloy functional properties. One of the solutions for preventing degradation in reactive chemical environments is encapsulating magnetic metal nanoalloys in a carbon-based shell. Additionally, carbonaceous shell has the advantage of isolating the particles to avoid/decrease close-proximity magnetic interactions.

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Graphite-coated nanoparticles can be prepared by several approaches including chemical vapor condensation, pyrolysis of organometallic compounds, catalytic decomposition of methane, high-temperature annealing of carbon-based materials and metal precursor mixtures, arc-discharge process, etc. These methods have several disadvantages like complex procedures and poor growth control of the graphite-coated nanoparticles, and, moreover, the efficiency of encapsulation of nanoparticles by graphite is low. One of the proven and feasible alternative methods is multilayered graphitic coating by chemical vapor deposition (CVD). Castrillón et al. (2012) applied this method for synthesizing FeNi-alloy, NiCo-alloy, and FeCoalloy systems (Castrillón et al. 2012, 2013). A carbon-deficient atmosphere is employed in this method to obtain ultra-small and non-agglomerated superparamagnetic nanoparticles which are also stable at room temperature. The morphology, microstructure, and compositional characterization of the synthesized nanoparticles is performed by bright field (BF), and HAADF-STEM imaging combined with EDS and EELS analysis using a probe aberration-corrected TEM operated at 300 kV. Fe50Co50 alloy nanoparticles coated with graphite is studied to understand the chemical and structural changes at atomic scale before and after heat treatment. The obtained results are important in understanding the affect of temperature on the resultant properties. This helps in correlating the chemical composition, structure, magnetic behavior, and the size of the obtained FeCo nanoparticles at a given temperature.

Magnetic Nanowires Magnetoresistive properties of spin-valves in spintronic nanodevices are highly sensitive to the structural and chemical configurations at the interface. Hence, the chemical and structural information at high spatial resolution is indispensable to understand and predict the diverse physical and chemical properties in nanodevices. Similarly, it is also crucial to determine the accurate chemical and structural arrangement in nanoscopic junctions to study and engineer novel nanostructures. In the case of nanoscopic junctions made up of magnetic materials, magnetoresistance is known to depend on the atomic scale structural characteristics of nanojunctions. The advantage of studying such nanojunctions in a TEM is that suspended nanowires can be formed and studied in situ inside the microscope. Chemical characterization of nanojunctions or nanowires is necessary specifically in the case of multi-element materials. Presence of impurity atoms at the nanojunctions such as oxygen or carbon can drastically influence their properties. Oxygen can oxidize the nanowire, while carbon is known to the possible reason for stabilization of anomalously long gold atomic chains. Chemical mapping with EELS using STEM is a routinely performed technique for atomic scale information. However, the chemical mapping of nanowires with