隨著石油短缺，太陽能等替代能源漸受重視。其中，染料敏化太陽電池(DSSC)因其製作方法簡單、成本低廉且具有良好的光電轉換效率，使各國研究團隊近年來積極投入發展。
本篇論文研究中，針對染料敏化太陽能電池之二氧化鈦染料吸附層，使用紫外光照射及酸溶液如鹽酸進行表面處理，提升電池之光電轉換效率。紫外光照射二氧化鈦使二氧化鈦產生光觸媒效應除去表面有機污染物，可增加染料吸附量，但同時改變染料中螯合基(COO－)與二氧化鈦鍵結的方式，降低電子傳輸效率。在紫外光照射之後使用鹽酸處理法，可保有染料原本鍵結方式，利於電子傳輸；除此之外，H＋離子也會吸附在二氧化鈦表面，對染料之COO－螯合基產生靜電力，更加提升染料吸附量，因此改進染料敏化太陽電池之效率。
我們也利用傅氏紅外光譜儀探討染料-二氧化鈦鍵結，電化學阻抗分析儀探討各界面內電阻，X射線光電子能譜儀探討元素比例與表面特性，紫外光-可見光吸收光譜儀探討吸收光譜，掃描式電子顯微鏡探討表面型態，電流-電壓曲線量測探討染料敏化太陽能特性與光電轉換效率。
實驗結果顯示，轉換效率從未處理的6.29%，經紫外光處理提升至6.71 %，若照射紫外光再以鹽酸容易處理更可達7.39 %。

Alternative energy sources such as solar energy have attracted an extensive interest in the petroleum shortage era. Among solar cells, dye-sensitized solar cell (DSSC) attracts the attention of widespread research teams because of the easy-production process, low cost, and good photon-to-electron conversion efficiency.
In this study, both UV and acid solution such as HCl are used to improve the efficiency of DSSC. The UV illumination can eliminate organic contaminates on TiO2 by photocatalysis and enhance the adsorption of dye molecules. Meanwhile, the coordination mode between TiO2 and dye could be changed and lower the electron transportation. If the HCl solution is used after UV illumination, the coordination mode can be preserved. Moreover, H+ from HCl can attract the COO－ anchoring group of dye by electrostatic force. It further increases the adsorption of dye and improves the DSSC efficiency.
The coordination mode was measured by Fourier-transform infrared spectrometer (FTIR). The internal resistance was measured by electrical impedance spectroscopy (EIS). The chemical properties were characterized by X-ray photoelectron spectroscopy (XPS). The light absorbance was measured by ultraviolet-visible spectroscopy (UV-Vis). The morphology was observed by field emission scanning electron microscope (FE-SEM). The performance of the cells was measured by a semiconductor device analyzer.
In our results, the conversion efficiency was improved from 6.29% of untreated one to 6.71 and 7.39% for UV and UV + HCl treated ones.

論文審定書 i
ACKNOWLEDGEMENT ii
摘　要 iii
ABSTRACT iv
Chapter 1 1
Introduction 1
1.1 Energy crisis 1
1.2 Solar energy 2
1.3 Photovoltaic cell performance 2
1.4 The three generations 5
1.5 Operation principle of the dye-sensitized solar cell 9
1.6 Motivation 11
1.6.1 Photocatalysis reaction on TiO2 surface by UV illumination 11
1.6.2 Preservation of Coordination mode 13
1.6.3 Acid treatment 15
Chapter 2 17
Experimental 17
2.1 Materials 17
2.2 Preparation of solution 18
2.2.1 Choice and preparation of acid solution 18
2.2.2 Preparation of dye solution 18
2.3 Choice of UV treated timing 19
2.3.1 UV illumination as dye anchoring 19
2.3.2 Double UV illumination as dye anchoring 21
2.3.3 UV illumination before dye anchoring 22
2.4 Fabrication of solar cell 24
2.4.1 Without treatment 24
2.4.2 UV treatment 25
2.4.3 UV + HCl treatment 26
2.4.4 UV + TiCl4 treatment 29
2.5 Measurement 31
Chapter 3 32
Results and discussion 32
3.1 UV treatment 32
3.1.1 Fourier-transform infrared spectrometer (FTIR) analysis 32
3.1.2 Electrical impedance spectroscopy (EIS) analysis 34
3.1.3 X-ray photoelectron spectra (XPS) analysis 35
3.1.4 Ultraviolet-visible spectrophotometer (UV-Vis) analysis 38
3.1.5 Proformance of DSSC 39
3.2 UV + HCl treatment 41
3.2.1 Fourier-transform infrared spectrometer (FTIR) analysis 41
3.2.2 Electrical impedance spectroscopy (EIS) analysis 43
3.2.3 X-ray photoelectron spectra (XPS) analysis 44
3.2.4 Ultraviolet-visible spectrophotometer (UV-Vis) analysis 46
3.2.5 Proformance of DSSC 47
Chapter 4 52
Conclusion 52
References 54
Chapter 1 54
Chapter 2 57
Chapter 3 58
Appendix 63
1. Introduction 63
A.1.1 Anti-reflection coating – “Moth eye” principle 63
A.1.2 Structure conditions for moth eye effect 63
A.1.3 Effective medium theories 64
A.1.4 Property of ASD-ZnO nanotip 66
2. Experimental 67
A.2.1 ZnO seed layer prepared by RF sputtering 67
A.2.2 Fabrication of DSSC 68
A.2.3 Growth of ASD-ZnO nanotip 69
3. Results and discussion 73
A.3.1 Effective refractive index 73
A.3.2 Performance of DSSC with ZnO nanotip 76
References 78

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