Title Page
Abstract
Contents
CHAPTER 1. Introduction 14
CHAPTER 2. Experimental and analysis 18
2.1. Electrochemical synthesis of rGO-Fe₃O₄ composite 18
2.2. physical characterization 19
2.3. Electrochemical measurements. 20
CHAPTER 3. Results & Discussion 21
3.1. Formation of the rGO-Fe₃O₄ complex and physical property assessment. 21
3.2. Electrochemical performances 35
CHAPTER 4. Conclusion 50
References 52
Table 1. zeta-potential measurement of p-rGO and Fe₃O₄. 23
Figure 1. (a) Schematic illustration of the preparation of rGO-Fe₃O₄ complex, (b) direct measurement of pH and concentration of electrolyte by... 22
Figure 2. (a)TEM and (b)HR-TEM images of rGO-Fe₃O₄ complex, and (c) TEM image with corresponding EDX mapping of oxygen, carbon, iron elements. 27
Figure 3. SEM images of rGO-Fe₃O₄ Complex. (a)before and (b) after thermal treatment. 29
Figure 4. (a) Raman spectrum and (b) XPS spectra for comparison rGO-Fe₃O₄ complex and p-rGO. (c) XPS Fe 2p spectra of rGO-Fe₃O₄ complex... 31
Figure 5. (a) the cycling performance at A g¯¹ of rGO-Fe₃O₄ electrode with various graphene ratio (0%, 20%, 30%, 40%, and 50%), (b) CV curves of the rGO-... 35
Figure 6. (a) The rate performance of rGO-Fe₃O₄, physical mixing of rGO and Fe₃O₄, and Fe₃O₄ electrode at various rates. (b) charge-discharge capacities of... 38
Figure 7. (a) CV curves of the rGO-Fe₃O₄ electrode at a scan rate of mV s-1 in the 25th, 50th, 75th, and 100th cycle. (b) galvanostatic discharge/charge curves of 1st,...[이미지참조] 40
Figure 8. Capacitive contribution and diffusion contribution of rGO-Fe₃O₄ electrode for comparison for (a, c, e, and g) 50th cycle and (b, d, f, and h) 100th...[이미지참조] 46
Figure 9. capacitive capacities contribution ratio at a different scan rate of (a) 50th cycle and (b) 100th cycle. 47