Mechanism of PbI2 in Situ Passivated Perovskite Films for Enhancing the Performance of Perovskite Solar Cells

• DOI: 10.1021/acsami.9b13648
• Publication Date: 2019-11-04T10:03:21Z
• Authors: Yichuan Chen; Qi Meng; Yueyue Xiao; Xiaobo Zhang; Junjie Sun; Chang Bao Han; Hongli Gao; Yongzhe Zhang; Yue Lu; Hui Yan
• Keywords: Passivation; Carrier lifetime; Perovskite solar cell

Perovskite solar cells (PSCs) have gained tremendous research interest because of their tolerance defects, low cost, and facile processing. In PSC devices, PbI2 has been utilized to passivate defects at perovskite film surfaces GBs; however, a systematic mechanism in situ passivation for enhancing the efficiency not fully explored. Here, this work, we systematically studies effect precise ratio based on trap density, carrier lifetime, Fermi level, so forth. This study finds appropriate I/Pb be around 2.57:1 using energy-dispersive spectroscopy. After moderate excess passivation, density is reduced from 6.12 × 1016 3.38 cm-3, lifetime extended 168.35 368.77 ps by fs-TA result indicates that can reduce suppress nonradiative recombination. The cell shown nearly 11.3% improvement 19.55% an compared with 2.69:1. It also demonstrates PSCs enhanced effectively passivation.