Constructing Chromium Multioxide Hole-Selective Heterojunction for High-Performance Perovskite Solar Cells

作者：Jiang, Sheng; Xiong, Shaobing; Dong, Wei; Li, Danqin; Yan, Yuting; Jia, Menghui; Dai, Yannan; Zhao, Qingbiao; Jiang, Kai^*; Liu, Xianjie; Ding, Liming^*; Fahlman, Mats; Sun, Zhenrong; Bao, Qinye^*

来源：Advanced Science, 2022, 9(30): 2203681.

DOI：10.1002/advs.202203681

• charge transport
• efficiency
• hole-selective heterojunction
• nonradiative recombination
• perovskite solar cells

Perovskite solar cells (PSCs) suffer from significant nonradiative recombination at perovskite/charge transport layer heterojunction, seriously limiting their power conversion efficiencies. Herein, solution-processed chromium multioxide (CrOx) is judiciously selected to construct a MAPbI(3)/CrOx/Spiro-OMeTAD hole-selective heterojunction. It is demonstrated that the inserted CrOx not only effectively reduces defect sites via redox shuttle at perovskite contact, but also decreases valence band maximum (VBM)-HOMO offset between perovskite and Spiro-OMeTAD. This will diminish thermionic losses for collecting holes and thus promote charge transport across the heterojunction, suppressing both defect-assisted recombination and interface carrier recombination. As a result, a remarkable improvement of 21.21% efficiency with excellent device stability is achieved compared to 18.46% of the control device, which is among the highest efficiencies for polycrystalline MAPbI(3) based n-i-p planar PSCs reported to date. These findings of this work provide new insights into novel charge-selective heterojunctions for further enhancing efficiency and stability of PSCs.

• 单位
  中国科学院; 国家纳米科学中心