藉由結合四氯化鈦處理多孔性二氧化鈦光電極以及新穎的高反射性對電極Pt/FTO/Al於染料敏化太陽能電池中來提升太陽電池的光電特性。實驗結果指出入射光會被四氯化鈦處理後得到的大粒徑二氧化鈦顆粒散射以及因高反射特性的對電極反射而進一步有效吸收光源。因此，相較於不經任何處理的標準電池而言，可以有效抑制光對電池元件的穿透情形。此外，經過改良的電池相較於標準電池在短路電流密度上提升34%，並且得到5.62%的光電轉換效率。在第二部份中，我們藉由四氯化鈦處理來改善二氧化鈦顆粒間的連結特性以及濺鍍鈦金屬薄膜於染料敏化太陽電池的導電玻璃來改善導電玻璃與多孔性二氧化鈦光電極的介面電阻，進而有效抑制電子與染料、電解液發生逆向複合的情形。實驗結果得出經過處理後的電池相較於標準電池在短路電流密度上提升42%，並且得到6.13%的光電轉換效率。此外，為讓太陽電池可廣泛應用，發展可撓式染料敏化太陽電池是必要的。我們以 PET-ITO基板做為光電極基板，利用不鏽鋼板做為對電極基板，成功製成可撓式染料敏化太陽電池，其光電轉換效率可達 2.27%。

This thesis attempts to enhance the performance of dye-sensitized solar cells (DSSCs) by integrating the TiCl4 treatment on porous TiO2 and a novel high-reflective counter electrode, Pt/FTO/Al. Experimental results indicate that light scattered by TiCl4-treated large TiO2 particle sizes and light reflected by the counter electrode decrease the total transmission of the modified cell. Additionally, the modified DSSCs significantly increase the short-circuit photocurrent density (Jsc) by about 34% higher than that of the standard cell, resulting in about 42% higher than that of a standard cell. In the next study, we focus on the DSSCs with the TiCl4 treatment and the Ti-deposited thin film metal on FTO of the enhancement of collection efficiency to improve cells. The modified DSSCs give the significantly improvement of the short-circuit photocurrent density (Jsc) about 42% greater than that of the standard cell, and resulting in a 6.13% energy conversion efficiency. Finally, we had fabricated a flexible DSSC, the substrate of photoelectrode was PET-ITO, and the substrate of counter electrode, and the conversion efficiency of flexible DSSC was 2.27%.

Chapter 1 Introduction
1.1 Background 1
1.2 Overview of Photovoltaic 2
1.3 Thesis Outline 3
Chapter 2 Dye-sensitized Solar Cells
2.1 Overview of Dye-Sensitized Solar Cell 7
2.2 Basic structures and principles of DSSCs 7
2.3 Component of DSSCs 9
2.4 Fundamental parameters of solar cell and analysis 13
2.5 Motivation 14
Chapter 3 Light harvesting enhancement of DSSCs by using TiCl4 treatment on porous TiO2 and high-reflective Pt/FTO/Al counterelecrode
3.1 Introduction 20
3.2 Experiment and DSSCs fabrication 22
3.3 Result and Discussion 24
3.4 Conclusions 27
3.5 Characteristic analysis and Experiment Equipment 28
Chapter 4 Enhance the collection efficiency of excited electron of DSSCs with Sputtered Ti Thin Film as an interfacial layer and TiCl4 treatment
4.1 Introduction 38
4.2 Experiment 39
4.3 Result and Discussion 40
4.4 Conclusions 43
4.5 Future work 44
Chapter 5 Flexible Dye-sensitized Solar Cell
5.1 Introduction 52
5.2 Application of metal thin-film on stainless steel substrate 53
5.3 The low temperature coated mesoscopic Titania onto the PET-ITO based Dye-sensitized electrodes 54
5.4 Result and Discussion 55
5.5 Conclusions 56
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