本論文旨在製備碳包覆二氧化鈦奈米結構,並應用於紫外光分解污染物與染料敏化太陽能電池中。我們以蔗糖為碳源,利用非水溶液溶膠-凝膠法製備碳包覆二氧化鈦奈米顆粒,並藉由控制合成條件與煅燒溫度,調控材料的結構與組成。我們以這些碳包覆奈米顆粒進行亞甲基藍的光解反應,發現其活性較商用二氧化鈦P25高出數倍。另外,我們也將碳包覆二氧化鈦奈米顆粒作為染料敏化太陽能電池的活性層,發現光電轉換效率較商用二氧化鈦ST21高。另一方面,我們在類似的非水溶液合成條件下,加入商用二氧化鈦作為晶種,製備出三維的二氧化鈦奈米結構,並利用它作為染料敏化太陽能電池的反射層,希望能提高電解質液的擴散效率,而能進一步提高光電轉換效率。
Carbon-coated titania nanostructures have been prepared for applications of methylene blue photodecomposition and dye-sensitized solar cells. The carbon-coated titania nanoparticles are synthesized by nonaqueous sol-gel route using sucrose as a carbon source. The structure and composition can be controlled by changing the synthetic conditions and pyrolysis temperature. The thus prepared carbon-coated titania nanoparticles can decompose methylene blue under UV irradiation with much higher rates than commercial P25 titania. When being used as active layer materials, the resulting dye-sensitized solar cells exhibit higher conversion efficiency than the cells using commercial ST-21 titania. Furthermore, the same synthesis strategy can be applied to prepare titania nanostructures by seeding growth. With unique three-dimensional morphology, the titania nanostructures are incorporated in dye-sensitized solar cells as scattering layer materials to enhance the diffusion efficiency of electrolyte and the conversion efficiency of the cell.