Interface Modification for Planar Perovskite Solar Cell Using Room-Temperature Deposited Nb2O5 as Electron Transportation Layer

作者：Yixin Guo, Jiahua Tao, Fuwen Shi, Xiaobo Hu, Zhigao Hu, Kezhi Zhang, Wenjuan Cheng, Shaohua Zuo, Jinchun Jiang, Junhao Chu · 发表于：ACS Applied Energy Materials · 年份：2018 · DOI：10.1021/acsaem.8b00094 · 被引用次数：50 · 研究领域：Perovskite Materials and Applications、Conducting polymers and applications、Organic Light-Emitting Diodes Research

Compared with crystallized TiO 2, amorphous Nb 2 O 5 has been applied in planar perovskite solar cell as electron transportation layer because of its excellent optical transmittance, low temperature preparation process, and similar Femi level with TiO 2 . However, the electron transfer rate is still limited by its low electron mobility and surface defect via room-temperature deposition process. Herein, a novel double buffer layer of [6,6]-phenyl-C61- butyric acid methyl ester(PCBM)/ionic liquid([EMIM]PF 6 ) has been inserted between perovskite and Nb 2 O 5 film. The PCBM could passive the surface of Nb 2 O 5 and improve electron extraction ability. The insert of [EMIM]PF 6 could improve the hydrophilic of PCBM and decrease the dissolution of PCBM in DMF during spin-coat perovskite precursor solution. A relatively high open voltage (over 1.09 V) and conversion efficiency of 18.8% have been achieved by using a double buffer layer which is the highest PCE of Nb 2 O 5 based perovskite solar cell to our best knowledge. The results indicate room temperature deposited Nb 2 O 5 can be a suitable candidate for replacing crystallized TiO 2 film and proposed modification strategy could facilitate the future development of interface modified layer for high efficient planar perovskite solar cell.