Room Temperature Crystallized Phase‐Pure α‐FAPbI3 Perovskite with In‐Situ Grain‐Boundary Passivation

• DOI: 10.1002/advs.202400275
• Publication Date: 2024-03-20T05:39:19Z
• Authors: Zejiao Shi; Yaxin Wang; Yanyan Wang; Xiaoguo Li; Xiaofei Yue; Haoliang Wang; Xin Zhang; Liangliang Deng; Chongyuan Li; Jiao Wang; Zuoti Xie; Yinguo Yang; Chunxiao Cong; Anran Yu; Yiqiang Zhan
• Keywords: Passivation; Phase boundary

Abstract Energy loss in perovskite grain boundaries (GBs) is a primary limitation toward high‐efficiency solar cells (PSCs). Two critical strategies to address this issue are high‐quality crystallization and passivation of GBs. However, the established methods generally carried out discretely due complicated mechanisms growth defect formation. In study, combined method proposed by introducing 3,4,5‐Trifluoroaniline iodide (TFAI) into precursor. The TFAI triggers union nano‐sized colloids microclusters facilitates complete phase transition α‐FAPbI 3 at room temperature. controlled chemical reactivity strong steric hindrance effect enable fixed location suppress defects This combination well‐crystallized grains effectively passivated GBs leads an improvement open circuit voltage ( V oc ) PSCs from 1.08 1.17 V, which one highest recorded without interface modification. TFAI‐incorporated device achieved champion PCE 24.81%. maintained steady power output near its maximum point, showing almost no decay over 280 h testing pre‐processing.