Title Page
Contents
List of Abbreviations 14
Abstract 16
Chapter 1. Introduction 19
1.1. Introduction 19
1.2. Research objective 25
1.3. Research outline 28
Chapter 2. Background 29
2.1. Overview of aqueous electrochemical energy storage 29
2.2. Overview of Zinc ion storage system 31
2.2.1. Introduction of Zinc ion batteries 31
2.2.2. Composition of Zn ion battery system. 32
2.2.3. Zn²⁺ Storage mechanism of Zinc ion batteries 32
2.3. Overview of flexible energy storage system 35
2.3.1. Introduction of flexible energy storage system 35
2.3.2. Purpose of flexible energy storage system 35
2.3.3. Market trends of flexible energy storage system 36
2.3.4. Limitation of current flexible energy storage system 36
2.3.5. Electrode materials for flexible energy storage system 37
2.4. Overview of components for Zn ion storage system 39
2.4.1. Electrode materials 39
2.4.2. Aqueous electrolyte 44
2.5. Perylene tetracarboxylic Dianhydride 46
Chapter 3. Design and synthesis control of organic material and CNT hybrid flexible film 48
3.1. Experiment 48
3.1.1. Synthesis of materials 48
3.1.2. Materials characterizations 51
3.2. Result and discussion 53
3.2.1. Synthesis and characterization of Hy-PTPA and Hy-PTPA@CNT film 53
3.2.2. Synthesis mechanism of Hy-PTPA and Hy-PTPA@CNT film 79
3.4. summary of chapter 84
Chapter 4. Organic material and CNT hybrid film for aqueous Zn-ion storage 85
4.1. Experiment 85
4.1.1. Electrochemical measurements 85
4.1.2. Capacity, energy density and power density calculations 88
4.2. Result and discussion 89
4.2.1. Electrochemical measurement of Hy-PTPA and Hy-PTPA@CNT film 89
4.2.2. Ex-situ measurements for revealing zinc ion storage mechanism of Hy-PTPA@CNT film electrode 100
4.2.3. Electrochemical measurement of flexible energy storage system using Hy-PTPA@CNT film 108
4.3. Summary of chapter 122
Conclusion 124
Reference 126
초록 132
Table.1. Comparison of charge carrier ions 30
Table.2. FT-IR Peak Assignment of materials 71
Fig. 1.1. Illustration of Research objective and outline. 27
Fig. 2.1. Schematic illustration of the working principle of rechargeable Zn-ion batteries. 34
Fig. 2.2. Chemical structure and visual appearance of PTCDA precursors. 47
Fig. 3.1. Schematic illustration of synthesis procedures for Hy-PTPA. 50
Fig. 3.2. Schematic illustration of synthesis procedures for Hy-PTPA@CNT film. 50
Fig. 3.3. SEM images of MWCNT, PTCDA percursor, Hy-PTPA nanorod and Hy-PTPA@CNT film. 54
Fig. 3.4. TEM images of MWCNT, PTCDA percursor, Hy-PTPA nanorod and Hy-PTPA@CNT film in high magnitude. 55
Fig. 3.5. TEM images of MWCNT, PTCDA percursor, Hy-PTPA nanorod and Hy-PTPA@CNT film in low magnitude. 56
Fig. 3.6. SEM images of cross section structures of Hy-PTPA@CNT film. 59
Fig. 3.7. Digital photos of Hy-PTPA@CNT film and flexibility test. 61
Fig. 3.8. Visual photograph depicting the comparison of color changes during the synthesis process from pristine PTCDA to Hy-PTPA. 62
Fig. 3.9. Solid ¹³C NMR result comparisons of PTCDA percursor, NaPT and Hy-PTPA. 65
Fig. 3.10. FT-IR result comparisons of CNT, PTCDA percursor and Hy-PTPA. 69
Fig. 3.11. FT-IR result comparisons of PTCDA percursor, Hy-PTPA and Hy-PTPA@CNT film. 70
Fig. 3.12. XRD result comparisons of CNT, PTCDA percursor and Hy-PTPA. 72
Fig. 3.13. XRD result comparisons of PTCDA percursor, Hy-PTPA and Hy-PTPA@CNT film. 73
Fig. 3.14. XRD result comparisons of Hy-PTPA@CNT films with different mass ratio between organic resion and CNT. 74
Fig. 3.15. TOF-SIMS result comparisons of CNT, PTCDA percursor and Hy-PTPA. 76
Fig. 3.16. XPS result comparisons of PTCDA percursor, Hy-PTPA, and Hy-PTPA@CNT film. 78
Fig. 3.17. Process of ring-opening reaction. 81
Fig. 3.18. Detailed mechanism of ring-opening reaction. 81
Fig. 3.19. Process of substitution reaction. 82
Fig. 3.20. Detailed mechanism of substitution reaction. 82
Fig. 3.21. Process of reassemble. 83
Fig. 3.22. Detailed mechanism of reassemble process. 83
Fig. 4.1. Flexible sandwich cell assembly schematic diagram. 87
Fig. 4.2. Electrochemical performance of PTCDA in potential range of 0.2~1.2 V, a) CV curve at 0.1 mV s⁻¹ sacn rate, b) CV curves at initial 10 times of... 92
Fig. 4.3. Electrochemical performance of Hy-PTPA in potential range of 0.2~1.2 V, a) CV curve at 0.1 mV s⁻¹ sacn rate, b) CV curves at initial 50 times of... 93
Fig. 4.4. Electrochemical performance of Hy-PTPA@CNT film in potential range of 0.2~1.2 V, a) CV curve at 0.1 mV s⁻¹ sacn rate, b) CV curves at initial 50 times... 94
Fig. 4.5. Comparison of EIS results between electrode material components. 96
Fig. 4.6. Rate capability of CNT, PTCDA, Hy-PTPA, Hy-PTPA@CNT film at various current densities from 0.1 to 10 A g⁻¹. 98
Fig. 4.7. Long-term stability of CNT, PTCDA, Hy-PTPA, Hy-PTPA@CNT film at 1 A g⁻¹, respectively. 99
Fig. 4.8. Initial charge-discharge curve of HyPT@CNT electrode recorded at the selected states during the first cycle. 101
Fig. 4.9. XRD patterns of HyPT@CNT electrode recorded at the selected states during the first cycle. 103
Fig. 4.10. FT-IR spectra of HyPT@CNT electrode recorded at the selected states during the first cycle. 105
Fig. 4.11. Ex-situ HR-TEM EDX mappings of HyPT@CNT electrode at initial state, fully discharged state and fully charged state, respectively. 107
Fig. 4.12. CV curves of the flexible sandwich type cell in potential range of 0.2~1.2 V at various sacn rates from 0.1 mV s⁻¹ to 10 mV s⁻¹. 110
Fig. 4.13. GCD profiles of the flexible sandwich type cell in potential range of 0.2~1.2 V at different current densities from 0.1 A g⁻¹ to 10 A g⁻¹. 111
Fig. 4.14. Nyquist plot of the flexible sandwich type cell. Inset, magnified plots of the high-frequency region. 112
Fig. 4.15. Long-term stability and coulombic efficiency of the flexible sandwich type cell in 180° folded state at a current denstity of 0.2 A g⁻¹. 113
Fig. 4.16. CV curves of the flexible sandwich type cell in potential range of 0.2~1.2 V with bending degrees from 0°to 180° at 0.1 mV s⁻¹ sacn rate. 116
Fig. 4.17. GCD profiles of the flexible sandwich type cell in potential range of 0.2~1.2 V with bending degrees from 0° to 180° at a current densities from... 117
Fig. 4.18. Rate capability measured 100 times while going back and forth from 0° to 180° at current density of 1 A g⁻¹. 118
Fig. 4.19. Nyquist plot curves measured while going back and forth from 0° to 180°. Inset, magnified plots of the high-frequency region. 119
Fig. 4.20. Rate performances at current density from 0.1 to 10 A g⁻¹ while folded 180°. 120
Fig. 4.21. Actual appearance of a flexible zinc ion energy storage system device measured while bending from 0° to 180°. 121