在碳六十衍生物中引入含不同相反離子團之四級銨鹽做為電子傳輸層以增進反結構鈣鈦礦太陽能電池之效率

Abstract

本研究中將含有不同相反離子的三種銨鹽，包含四丁基溴化銨、四丁基四氟硼酸銨和四丁基六氟磷酸銨引入[6,6]-苯基-C61-丁酸甲酯([6,6]-phenyl-C61 butyric acid methyl ester, PCBM)做為電子傳輸層。添加銨鹽的PCBM之電子遷移率和費米能階均較純PCBM為高。從螢光光譜淬熄分析中，亦可知添加銨鹽之PCBM與鈣鈦礦之間的介面有較好的電荷傳輸效果。本研究製作元件結構為ITO/PEDOT:PSS/CH3NH3PbI3/PCBM+salts/Ag之反結構鈣鈦礦太陽能元件，顯示使用添加銨鹽的PCBM作為電子傳輸層之元件JSC 和 FF均有明顯提升。最佳元件為PCBM添加TBABF4之鈣鈦礦元件，其效率達到13.41%，相較使用無摻雜PCBM之元件顯得更為優越。

In this research, three quaternary ammonium salts containing different counterions, including tetrabutylammonium bromide (TBABr), tetrabutylammonium tetrafluoroborate (TBABF4), and tetrabutylammonium hexafluorophosphate (TBAPF6), were incorporated into [6,6]-phenyl-C61 butyric acid methyl ester (PCBM) as electron transporting layer (ETL). These salts-doped PCBM films revealed higher electron mobility and Fermi levels compared with the un-doped one. Better charge transfer at the interface between perovskite and salts-doped PCBM was also obtained from PL quenching experiments. Inverted perovskite solar cells with the configuration of ITO/PEDOT:PSS/CH3NH3PbI3/PCBM+salts/Ag were fabricated, and the JSC and FF of devices were significantly enhanced using salts-doped PCBM as ETL. The best device based on TBABF4-doped PCBM delivered a power conversion efficiency (PCE) up to 13.41%, which was superior to the one with undoped PCBM layer (PCE = 8.77%).