鈣鈦礦太陽能電池(Perovskite Solar Cell，簡稱PSC)，光電轉換效率最高達24.2%(與矽晶圓太陽能電池的效率差不多)。以低溫方式所製備的TiO2(Lt-TiO2)膜作為一般式PSC的電子傳遞層(electron transporting layer，ETL)，雖然有利於低成本製造及軟性基材應用，但Lt-TiO2膜有高缺陷密度及低電子萃取能力之缺點，導致所組裝的一般式PSC有嚴重的遲滯現象，影響其商品化行程。本研究透過使用具有高導電度及醇溶性的富勒烯衍生物，如：C60-RT2、C60-RT6、C70-RT2作為添加劑，製備含富勒烯衍生物的TiO2的奈米複合物膜(Cx-RTy:Lt-TiO2)作為一般式PSC的電子傳遞層，結果以C60-RT6:Lt-TiO2為ETL之元件有最佳的光電轉換效率，C60-RT6的添加能增加Lt-TiO2 ETL的電子萃取能力、導電度，減少缺陷，增加緻密度及親水性。並使沈積在ETL上的鈣鈦礦(Psk)膜有較大顆粒。由於C60-RT6材料中胺基(R-NH3+)上的氫會與鈣鈦礦結構中I產生氫鍵作用力，因此沉積於C60-RT6:Lt-TiO2膜上的Psk膜的結晶度比沈積於Lt-TiO2上的高。不管C60-RT6:Lt-TiO2膜(含2.25 wt% C60-RT6的C60-RT6:Lt-TiO2)是在100℃或室溫下乾燥30分鐘所製備的，尤其為ETL所組裝成PSC元件的光電轉換效率分別為17.99%(室溫乾燥)及17.51%(100℃加熱乾燥)均比其相同條件下製備的純Lt-TiO2膜為ETL的元件之光電轉換效率分別為14.47%及15.52%高，且元件的遲滯現象小，在手套箱中的長時間穩定性也較好。;Perovskite Solar Cell (PSC) has a power conversion efficiency of up to 24.2% (close to the efficiency of silicon wafer based solar cells). The TiO2 (Lt-TiO2) film prepared by low temperature method used as the electron transporting layer (ETL) in the regular PSC has the advantage of low-cost fabrication and flexible substrate applicable, nevertheless, it also has defect density. Furthermore Lt-TiO2 also has low electron extraction ability, resulting in a serious current hysteresis of the corresponding regular PSC. In this study, the fullerene derivatives (such as C60-RT2, C60-RT6, and C70-RT2) with alcohol solubility were prepared to be an additive for Lt-TiO2 electron transporting material (ETM). The additive all improve the photovoltaic performance of Lt-TiO2 ETL and amongst these three fullerene derivatives, C60-RT6 has the best performance. Comparing to Lt-TiO2 film, C60-RT6:Lt-TiO2 nanocomposite film has better electron extraction ability、higher conductivity、less defects and more hydrophilic no matter the ETL was heated at 100°C or dried at ambient atmosphere for 30 minutes. As a result perovskite (Psk) film deposited on the C60-RT6:Lt-TiO2 nanocomposite film has larger particles and better crystallinity than that deposited on Lt-TiO2 ETL. The power conversion efficiencies of the regular PSC besed on C60-RT6:Lt-TiO2 nanocomposite ETL increases to 17.99% (when the ETL was dried at room temperature) and 17.51% (ETL was heated at 100°C) respectively which are higher than those (14.47% and 15.52%, respectively) of the cells based on pure Lt-TiO2 ETL prepared under the same conditions. At the same time the current hysteresis is smaller and the long-term stability in the glove box is better for the cell based on C60-RT6:Lt-TiO2 nanocomposite ETL compared to those using Lt-TiO2 ETLs.
