Multi‐Hydroxyl and Chloric Buried Interface Bridges Enable Synergistically High‐Efficiency Perovskite Solar Cells
Shuping Xiao, Jiyuan Gao, Bingxin Ding, Bobo Yuan, Yiheng Gao, Qingbo Liu, Zhongli Qin, Hong Tao, Liang Ma, Weijun Ke, Guojia Fang, Pingli Qin
Abstract
Abstract Defects at the interface between perovskite and carrier transport layer are ≈100 times more prevalent than those within perovskite bulk, potentially serving as non‐radiative recombination centers to adversely affect carrier extraction and transport. Here, a green pyridoxine hydrochloride (PDHC) is introduced into SnO 2 quantum dots (QDs) solution. The resulting surface chloritization of SnO 2 QDs not only passivates the interface defects, thereby strengthening the interface contact among SnO 2 QDs, but also chemically interconnects SnO 2 QDs with perovskite, thereby forming a very stable interlayer. These promote to establish the carrier transport bridges at the buried interfaces for efficient electron‐transportation and ‐extraction. Under its organic group coordination, high‐quality perovskite films are formed via heterogeneous nucleation on the perovskite precursor film, effectively suppressing bulk defects, which mitigates the nonradiative recombination and extends the carrier lifetime. Consequently, the PDHC‐based perovskite solar cells achieve an improved efficiency from 24.18 to 25.07%. After 2520 h storage, the unencapsulated devices retained ≈90% of their initial efficiency, exceeding those of control devices which retained only 65% of their initial efficiency, along with 9.4 and 3.8‐fold improvement for thermal and light stability.