本研究藉由將液晶分子(Liquid Crystal)摻入染料敏化太陽能電池中的液態電解液成功提升染料敏化太陽能電池的效率。當液晶分子散佈在液態電解液當中，由於液晶分子不均勻排列造成的折射率不匹配會導致光散射的產生，光散射的特性允許太陽光在元件內部的有更長的行進路徑，因此提高了N719染料的光捕獲效率。而且從實驗結果發現當添加液晶分子的濃度為20%時，染料敏化太陽能電池聚有最佳的元件光電轉效率。

此外，本研究也將膽液晶分子摻入染料敏化太陽能電池中的液態電解液，並且與摻入一般液晶的染料敏化太陽能電池比較。膽固醇液晶具有週期性螺旋排列的結構，當存在於電解液中，除了能維持光散射的特性，同時也具有選擇性反射的性質。因此相較與摻入一般液晶的染料敏化太陽能電池，將膽固醇液晶分子摻入的染料敏化太陽能電池結合光散射以及反射的效應，具有更佳的N719染料光捕獲效率。再者，當膽固醇的反射波段(480~580nm)與光電極中N719染料分子特徵吸收峰值相匹配時，染料敏化太陽能電池的染料激發將提高，使太陽能電池有更佳的表現。

The study proposed a high efficient dye sensitize solar cell (DSSC) by embedding liquid crystal in liquid electrolyte. When liquid crystal molecules was disperse in the liquid electrolyte, the light-scattering occur due to refractive index mismatching by randomly oriented liquid crystal droplets. The light-scattering allows solar light have longer optical path length within the solar cell and therefore enhances light-trapping efficiency of N719 dye. The experiment results reveal that the DSSC with the liquid crystal concentration of 20 wt% have best electric conversion efficiency.
Moreover, the study also introduces chloseteric liquid crystal to the liquid electrolyte of a DSSC and compare with nematic liquid crystal embedded DSSC. The cholesteric liquid crystal with periodic helical structure in the liquid electrolyte provides not only light-scattering but also selective reflection. Compared with nematic liquid crystal embedded DSSC, the cholesteric liquid crystal embeded DSSC has a more large light-trapping efficiency due to combined effects of light scattering and selective reflection. Besides, when the reflective band (480~580nm) of cholesteric liquid crystal is matched to the absorption spectrum of N719 dye, the DSSC has better photoexcitation of dye and photovoltaic performance.

摘要 i
Abstract ii
目錄 iii
圖目錄 vi
表目錄 ix
第一章 序 1
第二章 染料敏化太陽能電池與液晶介紹 2
2.1無機太陽能電池 2
2.2 有機太陽能電池 2
2.3染料敏化太陽能電池結構與原理 3
2.3.1染料敏化太陽能電池 3
2.3.2透明導電基板(TCO substrate) 4
2.3.3緻密層(Dense layer) 4
2.3.4二氧化鈦電極(TiO2光電極) 4
2.3.5染料 6
2.3.6電解液 7
2.3.7對電極(鉑電極) 7
2.4 染料敏化太陽能電池之工作原理 8
2.5 太陽能電池的性能參數 9
2.6液晶的介紹 11
2.6.1液晶分類 12
2.6.2液晶物理特性 14
2.6.3 PDLC(Polymer-Dispersed Liquid crystal)之簡介 17
第三章 文獻回顧與研究動機 20
3.1文獻回顧 20
3.2 研究動機 27
第四章 實驗方法與製程 29
4.1 設備介紹 29
4.1.1紫外與可見光光譜儀(UV-Vis spectrometer) 29
4.1.2 旋轉塗佈機(Spin Coating machine) 29
4.1.3高溫爐(high temperature furnace) 30
4.1.4太陽光譜模擬量測系統(solar simulator system) 31
4.1.5光電轉換效率量測系統(IPCE system) 33
4.1.6偏光顯微鏡(Polarizing microscop) 33
4.2材料介紹 34
4.2.1製作TiO2光電極層主要材料及染料 34
4.2.2自製電解液材料和所使用液晶材料、旋性物質及特性簡單說明 34
4.3 DSSC元件樣品製程 36
4.3.1 ITO基板的清潔流程 36
4.3.2配製TiO2緻密層溶液 36
4.3.3配製標準TiO2溶膠凝膠溶液 36
4.3.4配製標準電解液 37
4.3.5 TiO2光電極層製作 38
4.3.6高溫鍛燒與定義工作面積 40
4.3.7配製染料與浸泡 41
4.3.8 DSSC元件封裝 42
4.3.9注入電解質 43
4.3.10測量效率 44
第五章 實驗結果與討論 45
5.1摻液晶後的電解液光學特性之探討 45
5.2液晶分子相分離聚集程度影響元件效率參數之探討 47
5.3 不同款式液晶分子摻入電解液影響元件參數之探討 53
5.4 膽固醇液晶摻入電解液之特性探討 55
第六章 結論與未來工作 63
6.1結論 63
6.2未來工作 63
第七章 參考文獻 65

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