Graphene Oxide (eBook)

Dr. Wei Gao is a newly started Assistant Professor in the Textile Engineering, Chemistry & Science Department at North Carolina State University. She worked as a Director’s Postdoctoral Fellow on fuel cells and batteries in Los Alamos National Laboratory for the past two years. She obtained her Ph.D. in chemistry from Rice University in 2012, under the guidance of Professor Pulickel M. Ajayan. She also holds M.S. in analytical chemistry and B.S. in chemistry from Nanjing University, China. Dr. Gao has several years of research experience in nanomaterials and nanotechnologies. Her Ph.D. thesis mainly focused on a group of new materials named “graphene oxides” and their applications in fuel cells and batteries, as well as water purification systems. Her future research interests lie at the interfaces between nanotechnology development and textile engineering. Dr. Gao is also very enthusiastic about teaching. She received the Harry B. Weiser Teaching Award from Rice University when she served as a teaching assistant in the organic chemistry lab course. She also volunteered as a Judge in Science Fairs at several local high schools, a presenter on fuel cell topics to female students in the Expanding Your Horizons 2014 mini-conference in Santa Fe and a Chinese teacher for two semesters at a local church in Los Alamos.Dr. Gao’s unique experience in carbon nanomaterial research, synthetic and analytical chemistry, as well as device design and fabrication inspires her plans for attaining better understanding and improved tailoring of nanomaterials for innovative energy-related systems. She wants to accomplish her research goals by engineering materials at the molecular level that promises to direct improvements in bulk properties such as the active surface area, chemical stability, and electronic/ionic conductivity, making them far superior to those of the current carbon-based materials.

Contents 6
Abbreviations 8
Chapter 1: Synthesis, Structure, and Characterizations 10
1.1 Introduction 10
1.2 Synthesis 12
1.2.1 Brodie Method and Staudenmaier Method 12
1.2.2 Hummers Method and Its Modifications 13
1.2.3 Tour Method and Discussions 15
1.2.3.1 Tour Method 15
1.2.3.2 Discussions 15
1.3 Spectroscopic Characterizations and Chemical Structure 18
1.3.1 Spectroscopic Characterizations 18
1.3.1.1 Solid-State13C Nuclear Magnetic Resonance (SSNMR) Spectroscopy 18
1.3.1.2 Diffuse Reflectance Infrared Fourier Transform (DRIFT) Spectroscopy 20
1.3.1.3 Raman, UV–Vis, XRD, and XPS 23
1.3.2 Chemical Structure 24
1.3.3 Structure Degradation 27
1.4 Morphological Characterizations and Thermal Stability 28
1.4.1 Transmission Electron Microscopy (TEM) and Scanning Transmission Electron Microscopy (STEM) 28
1.4.2 Atomic Force Microscopy (AFM) and Scanning Tunneling Microscopy (STM) 30
1.4.3 Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC) 31
1.5 Concluding Remarks 33
References 34
Chapter 2: Spectroscopy and Microscopy of Graphene Oxide and Reduced Graphene Oxide 38
2.1 Graphene, GO, and rGO 39
2.1.1 Physical Properties of Graphene, GO, and rGO 39
2.1.2 Optical Properties of Graphene, GO, and rGO 41
2.2 Single-GO Sheet Absorption Microscopy/Spectroscopy 43
2.3 Single-GO Sheet Emission Microscopy/Spectroscopy 47
2.4 GO Photoreduction 50
2.5 Single-rGO Sheet Absorption Microscopy/Spectroscopy 54
2.6 GO Photoreduction Mechanism 56
2.6.1 GO Photolysis 57
2.6.2 Kinetics/Energetics of Photolysis 58
2.6.3 Photolytic Reduction Mechanism 59
2.7 Temporal/Spatial Evolution of Photolysis 61
2.8 Conclusions 65
References 66
Chapter 3: The Chemistry of Graphene Oxide 70
3.1 Reduction 70
3.1.1 Comparison of Reduction Recipes 71
3.1.2 Theoretical Simulations and Predictions 82
3.2 Functionalization 84
3.2.1 Covalent 84
3.2.2 Non-covalent 88
3.3 Cross-linking 89
3.4 Doping 92
3.5 Toxicity and Hygroscopicity 93
3.5.1 Toxicity 93
3.5.2 Hygroscopicity 94
3.6 Concluding Remarks 94
References 95
Chapter 4: GO/rGO as Advanced Materials for Energy Storage and Conversion 105
4.1 GO/rGO-Derived Nonprecious Metal Catalysts 106
4.1.1 Overview 106
4.1.2 Heteroatom-Doped rGO Catalysts 108
4.1.2.1 Nitrogen-Doped rGO Catalysts 108
4.1.2.2 Other Heteroatom-Doped rGO Catalysts 113
4.1.3 Transition Metal-Doped rGO Catalysts 116
4.1.4 rGO/Oxide Hybrids Catalysts 117
4.2 GO/rGOs in Supercapacitors 122
4.3 GO/rGO Anodes in Li-Ion Batteries 127
4.4 Summary and Perspective 130
References 131
Chapter 5: Graphene Oxides in Filtration and Separation Applications 136
5.1 Introduction to Molecular Filtration and Separation 136
5.2 Structures of GO and GO Membranes 138
5.2.1 Atomic Structures of Graphene Oxide 138
5.2.2 Microstructures of Multilayer Graphene Oxide Membranes 140
5.3 Mechanisms of Selective Molecular Transport in Graphene Oxide Membranes 142
5.3.1 Selective Transport of Liquid and Gas 143
5.3.2 Selective Ion Transport 145
5.4 Recent Progresses in the Experimental Demonstrations Towards Applications 147
5.4.1 Water Purification 147
5.4.2 Ion Separation 148
5.4.3 Gas Separation 150
5.5 Conclusive Remarks and Perspectives 151
References 152