Multidentate Chelation Heals Structural Imperfections for Minimized Recombination Loss in Lead‐Free Perovskite Solar Cells

作者:Liu Gengling; Zhong Yang; Feng Wenhuai; Yang Meifang; Yang Guo; Zhong JunXing; Tian Tian; Luo JianBin; Tao Junlei; Yang Shaopeng; Wang XuDong; Tan Licheng; Chen Yiwang; Wu WuQiang
来源:Angewandte Chemie, 2022, 134(40).
DOI:10.1002/ANGE.202209464

摘要

Tin‐based perovskite solar cells (Sn‐PSCs) have emerged as promising environmentally viable photovoltaic technologies, but still suffer from severe non‐radiative recombination loss due to the presence of abundant deep‐level defects in the perovskite film and under‐optimized carrier dynamics throughout the device. Herein, we healed the structural imperfections of Sn perovskites in an “inside‐out” manner by incorporating a new class of biocompatible chelating agent with multidentate claws, namely, 2‐Guanidinoacetic acid (GAA), which passivated a variety of deep‐level Sn‐related and I‐related defects, cooperatively reinforced the passivation efficacy, released the lattice strain, improved the structural toughness, and promoted the carrier transport of Sn perovskites. Encouragingly, an efficiency of 13.7?% with a small voltage deficit of ≈0.47?V has been achieved for the GAA‐modified Sn‐PSCs. GAA modification also extended the lifespan of Sn‐PSCs over 1200?hours.(#br)Chemical modification of tin perovskites by biocompatible multidentate chelators realized “inside‐out” healing of structural imperfections and manipulation of carrier dynamics, delivering an efficiency up to 13.70?% with enhanced long‐term stability over 1200?h.