奈米TiO2薄膜的光電極是影響染料敏化太陽能電池光電特性的重要因素。本研究主要改善染料敏化太陽能電池中之工作電極暗電流的產生，所以在TiO2工作電極中添加具有良好導電性之材料，進而增進染料敏化太陽能電池的效率。在製備二氧化鈦漿料過程中分別添加石墨及還原氧化石墨烯兩種良好導電性的材料，使DSSC之短路電流密度(short-circuit current density)增加，進而提升DSSC的光電轉換效率。製備TiO2-Graphite、TiO2-G+rGO和TiO2-rGO漿料，作為染料敏化太陽能電池(DSSC)中之光電極材料。在DSSC光電極的製備上使用旋轉塗佈法塗佈在ITO導電玻璃上。經過太陽能光電轉換效率的測試結果顯示，添加石墨及還原氧化石墨烯粉末可以增加電池短路電流密度(Jsc)，塗佈TiO2-Graphite讓DSSC的光電轉換效率從原先之2.248 %最高提升到3.572 %；塗佈TiO2-rGO讓DSSC的光電轉換效率從原先之2.248 %最高提升到6.409 %；塗佈TiO2-G+rGO讓DSSC的光電轉換效率從原先之2.248%最高提升到4.582%。

The nanocrystalline-TiO2 film is a crucial factor of photoelectrode performances in dye-sensitized solar cells. In this study, we decreased dark current generation in the working electrode of the dye-sensitized solar cells. By adding good conductivity materials into TiO2 working electrode and thereby enhanced the efficiency of solar cells.During the preparation we added graphite and reduced graphene oxide that are well-conductive materials, since graphite and rGO can increase the short-circuit current density of DSSC therefore reduce the dark current generation, thus the light-to-electricity conversion effectively of DSSC can be effectively raised. The DSSC photoelectrodes were prepared by spin coating on ITO substrates. According to light-to-electricity conversion efficiency test, adding TiO2-Graphite, TiO2-Graphite-rGO and TiO2-rGO could increase the values of short-circuit current density (Jsc) obviously, and also improved the light-to-electricity conversion efficiency from 2.248 % to 3.572% by TiO2-Graphite, 6.409% by TiO2-rGO and 4.582% by TiO2-Graphite-rGO.

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