钙钛矿(结构)
紫外线
材料科学
原位
紫外线
化学工程
纳米晶
纳米技术
图层(电子)
光电子学
化学
有机化学
工程类
作者
Wanpei Hu,Zhiling Wen,Yu Xin,Peisen Qian,Weitao Lian,Xingcheng Li,Yanbo Shang,Xiaojun Wu,Tao Chen,Yalin Lu,Mingtai Wang,Shangfeng Yang
标识
DOI:10.1002/advs.202004662
摘要
Abstract Low‐temperature solution‐processed TiO 2 nanocrystals (LT‐TiO 2 ) have been extensively applied as electron transport layer (ETL) of perovskite solar cells (PSCs). However, the low electron mobility, high density of electronic trap states, and considerable photocatalytic activity of TiO 2 result in undesirable charge recombination at the ETL/perovskite interface and notorious instability of PSCs under ultraviolet (UV) light. Herein, LT‐TiO 2 nanocrystals are in situ fluorinated via a simple nonhydrolytic method, affording formation of Ti─F bonds, and consequently increase electron mobility, decrease density of electronic trap states, and inhibit photocatalytic activity. Upon applying fluorinated TiO 2 nanocrystals (F‐TiO 2 ) as ETL, regular‐structure planar heterojunction PSC (PHJ‐PSC) achieves a champion power conversion efficiency (PCE) of 22.68%, which is among the highest PCEs for PHJ‐PSCs based on LT‐TiO 2 ETLs. Flexible PHJ‐PSC devices based on F‐TiO 2 ETL exhibit the best PCE of 18.26%, which is the highest value for TiO 2 ‐based flexible devices. The bonded F atoms on the surface of TiO 2 promote the formation of Pb─F bonds and hydrogen bonds between F − and FA/MA organic cations, reinforcing interface binding of perovskite layer with TiO 2 ETL. This contributes to effective passivation of the surface trap states of perovskite film, resulting in enhancements of device efficiency and stability especially under UV light.
科研通智能强力驱动
Strongly Powered by AbleSci AI