Graphene Oxide

Due to its unique properties, graphene oxide has become one of the most studied materials of the last decade and a great variety of applications have been reported in areas such as sensors, catalysis and biomedical applications. This comprehensive volume systematically describes the fundamental aspects and applications of graphene oxide. The book is designed as an introduction to the topic, so each chapter begins with a discussion on fundamental concepts, then proceeds to review and summarize recent advances in the field. Divided into two parts, the first part covers fundamental aspects of graphene oxide and includes chapters on formation and chemical structure, characterization methods, reduction methods, rheology and optical properties of graphene oxide solutions. Part Two covers numerous graphene oxide applications including field effect transistors, transparent conductive films, sensors, energy harvesting and storage, membranes, composite materials, catalysis and biomedical applications. In each case the differences and advantages of graphene oxide over its non-oxidised counterpart are discussed. The book concludes with a chapter on the challenges of industrial-scale graphene oxide production. Graphene Oxide: Fundamentals and Applications is a valuable reference for academic researchers, and industry scientists interested in graphene oxide, graphene and other carbon materials.

Autorentext

Dr. Ayrat M. Dimiev, EMD Performance Materials, Darmstadt, Germany.
Since 2009, Dr Dimiev has been working very closely with graphene oxide and other graphitic carbon nanomaterials. He spent five years at Rice University studying fundamental aspects of graphene oxide, resulting in several ground-breaking papers in highly ranked journals including Nature and Science, followed by a period at AZ Electronic Materials where he worked on optimizing mass production of graphene oxide, and on developing novel graphene oxide applications. Dr Dimiev currently works at EMD Performance Materials, a business of Merck KGaA, in Darmstadt, Germany.

Dr. Siegfried Eigler, Chalmers University of Technology, Department of Chemistry and Chemical Engineering, Göteborg, Sweden
Dr Eigler received his PhD in organic chemistry from the Friedrich-Alexander-Universit t Erlangen-Nürnberg in 2006 under the guidance of apl. Prof. Dr. Norbert Jux. Subsequently he conducted basic research on electrically conductive polymers and graphene oxide as an industry chemist. In 2011 he became a lecturer and research associate at the Friedrich-Alexander-Universität Erlangen-Nürnberg, where he did habilitation and in 2016 he became Associate Professor at the Chalmers University of Technology. His research focuses on the controlled chemistry of graphene.

Inhalt

About the Editors xi

List of Contributors xiii

Foreword xv

Preface xvi

Part I Fundamentals 1

**1 Graphite Oxide Story From the Beginning Till the Graphene Hype 3
Anton Lerf

1.1 Introduction 3

1.2 Preparation of Graphite Oxide 5

1.2.1 Trials for Improving and Simplifying GO Preparation 5

1.2.2 OverOxidation of Graphite 8

1.2.3 Formation Mechanism First Approximation 9

1.3 Discovery of Essential Functional OContaining Groups and its Relation to the Development of Structural Models 10

1.3.1 Analytical Composition of Graphite Oxide 10

1.3.2 Creation of the Structural Model from 1930 till 2006 11

1.3.3 Considerations for the Formation Mechanism Second Approximation 16

1.4 Properties of Graphite Oxide 18

1.4.1 Thermal Degradation and its Products 18

1.4.2 Chemical Reduction Reactions 19

1.4.3 Reactions with Acids and Bases 21

1.4.4 Osmotic Swelling: Hydration Behavior and Colloid Formation 22

1.4.5 GO Acidity 23

1.4.6 Intercalation and Functionalization Reactions 26

1.4.7 Functional Groups, their Reactions and their Relation to GO Formation and Destruction 28

1.5 Epilogue 29

References 30

**2 Mechanism of Formation and Chemical Structure of Graphene Oxide 36
Ayrat M. Dimiev

2.1 Introduction 36

2.2 Basic Concepts of Structure 37

2.3 Preparation Methods 39

2.4 Mechanism of Formation 41

2.4.1 Theoretical Studies and System Complexity 41

2.4.2 Step 1: Formation of Stage1 H 2 So 4 GIC Graphite Intercalation Compound 42

2.4.3 Step 2: Transformation of Stage1 H 2 So 4 GIC to Pristine Graphite Oxide 43

2.4.4 Pristine Graphite Oxide Structure 45

2.4.5 Step 3: Delamination of Pristine Graphite Oxide 47

2.5 Transformation of Pristine Graphite Oxide Chemical Structure Upon Exposure to Water 47

2.6 Chemical Structure and Origin of Acidity 51

2.6.1 Structural Models and the Actual Structure 51

2.6.2 Origin of Acidity and the Dynamic Structural Model 57

2.7 Density of Defects and Introduction of OxoFunctionalized Graphene 64

2.7.1 OxoFunctionalized Graphene by CharpyHummers Approach 65

2.7.2 OxoFunctionalized Graphene from Graphite Sulfate 69

2.8 Addressing the Challenges of the TwoComponent Structural Model 72

2.9 Structure of Bulk Graphite Oxide 76

2.10 Concluding Remarks 80

References 81

**3 Characterization Techniques 85
Siegfried Eigler and Ayrat M. Dimiev

3.1 Nuclear Magnetic Resonance Spectroscopy of Graphene Oxide 85

3.1.1 Nuclear Magnetic Resonance Spectroscopy in Solids 85

3.1.2 Nuclear Magnetic Resonance Spectroscopy of Graphene Oxide 87

3.1.3 Discussion 92

3.2 Infrared Spectroscopy 93

3.3 Xray Photoelectron Spectroscopy 97

3.4 Raman Spectroscopy 100

3.4.1 Introduction 101

3.4.2 Raman Spectroscopy on Molecules 101

3.4.3 Raman Spectroscopy on Graphene, GO and RGO 101

3.4.4 Defects in Graphene 103

3.4.5 Raman Spectra of GO and RGO 104

3.4.6 Statistical Raman Microscopy (SRM) 109

3.4.7 Outlook 110

3.5 Microscopy Methods 111

3.5.1 Scanning Electron Microscopy 113

3.5.2 Atomic Force Microscopy 114

3.5.3 Transmission Electron Microscopy 115

3.5.4 HighResolution Transmission Electron Microscopy 115

References 118

**4 Rheology of Graphene Oxide Dispersions 121
Cristina Vallés

4.1 Liquid Crystalline Behaviour of Graphene Oxide Dispersions 121

4.1.1 Liquid Crystals and Onsager's Theory 121

4.1.2 Nematic Phases in Carbon Nanomaterials 122 4.2 Rheological Behaviour of Aqueous...