In-situ boundary bridging unlocks multi-grain-domain carrier diffusion in polycrystalline metal halide perovskites

作者：Minhuan Wang, Yanfeng Yin, Pengfei Wang, Wenzhe Shang, Yaling Han, Jing Gao, Kangshuo Hui, Tao Feng, Ummugulsum Gunes, Tristan Georges, Lyndon Emsley, Peng Xu, Jiming Bian, Jing Cao, Zhehan Ying, Rui Cai, Jingyi Xiao, Shengye Jin, Xiaoqing Jiang, Shaik M. Zakeeruddin, Wenming Tian, Likai Zheng, Yantao Shi, Michaël Grätzel · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-63777-5 · 被引用次数：3 · 研究领域：Perovskite Materials and Applications、Solid-state spectroscopy and crystallography、Advanced Thermoelectric Materials and Devices

Charge transport and extraction in polycrystalline perovskite films are often hindered by inefficient carrier transfer across grain domain boundaries (GDBs). Herein, we present a universal post-treatment strategy leveraging supramolecular crown ether-assisted slow release and precise delivery of Rb⁺ cations to GDBs, achieving in-situ GDB bridging. The solid-state nuclear magnetic resonance (NMR), transmission electron microscopic (TEM), and time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses confirm that Rb+ forms a non-perovskite phase, primarily localized at the surface and GDBs. Ultrafast time-resolved photoluminescence mapping revealed accelerated carrier diffusion across the grain boundaries for the Rb+-treated perovskite thin films which enables photo-generated charge carriers to travels over two grain domain boundaries before recombination. As a result, perovskite solar cells treated with this strategy achieved a champion efficiency of 26.02% (certified as 25.77%) and demonstrated remarkable stability, retaining 99.2% of their initial efficiency after 1300 h of continuous one-sun illumination under maximum power point tracking (ISOS-L-1I). Charge transport and extraction in polycrystalline perovskite films are often hindered by inefficient carrier transfer across grain domain boundaries (GDBs). Here, authors employ supramolecular assisted Rb+ delivery for in-situ GDB bridging, achieving efficiency of 26.02% for perovskite solar cells.