Fluoroacetate‐Mediated Dual‐Interface Ionic Stabilization in Perovskite Solar Cells
Abstract
ABSTRACT Crystallization kinetics and ionic dynamics jointly govern the efficiency and stability of perovskite solar cells (PSCs). Here, we report a fluoroacetate‐mediated molecular strategy that regulates perovskite crystallization and ionic migration. Ethylammonium trifluoroacetate (EATFA) coordinates with lead and formamidinium ions, accelerating nucleation and moderating grain growth during the vacuum quenching process. Upon annealing, EATFA localizes at both top and bottom interfaces, where dual‐sided enrichment passivates deep‐level traps, enhances charge extraction, and suppresses light‐induced halide accumulation. Deep‐level transient spectroscopy (DLTS) and transient ion drift (TID) reveal that EATFA prevents the temperature‐induced transition of iodide ions into an interstitial‐mediated migration pathway observed in conventional films (activation energy decreased from 0.47 to 0.15 eV). Applied to 1.66‐eV wide‐bandgap PSCs, critical for silicon/perovskite tandems yet prone to ion‐migration degradation, this strategy enhances both power‐conversion efficiency (PCE) and operational stability under thermal, ultraviolet, and continuous stress, achieving 22.06% PCE in 1‐square‐centimeter blade‐coated devices and retaining 95% of initial efficiency after 2000 h of maximum‐power point tracking and 91% after 1000 h at 65°C. Similar improvements in 1.55‐eV perovskites confirm the bandgap‐independent nature of this approach, providing a unified route toward efficient and durable PSCs.
Article Details
Authors (16)
Huitian Guo
Key Laboratory of Precision and Intelligent Chemistry Department of Materials Science and Engineering University of Science and Technology of China Hefei China
Fengchun Cai
Key Laboratory of Precision and Intelligent Chemistry Department of Materials Science and Engineering University of Science and Technology of China Hefei China
Lianyou Tang
State Key Laboratory of Precision and Intelligent Chemistry Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Hefei China
Yixuan Che
Hefei National Research Center for Physical Sciences at the Microscale
Hongguang Meng
State Key Laboratory of Photoelectric Conversion and Utilization of Solar Energy, Qingdao New Energy Shandong Laboratory, Qingdao Institute of Bioenergy and Bioprocess Technology
Minghui Li
Shaojie Yuan
Wuhan National Laboratory for Optoelectronics, School of Integrated Circuits, Huazhong University of Science and Technology 1 , Wuhan 430074,
Kaitian Mao
Key Laboratory of Precision and Intelligent Chemistry Department of Materials Science and Engineering University of Science and Technology of China Hefei China
Zhengjie Zhu
Feiyang Liu
Weiwei Chen
Yusong Wang
Chuanxiao Xiao
Haifeng Lv
Xiaojun Wu
Jixian Xu
State Key Laboratory of Precision and Intelligent Chemistry Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of China Hefei China