Tin-based perovskites are promising alternative materials to address the toxicity problems of lead-based perovskites. However, compared with mature lead-based perovskites, the poor stability and low photoluminescence quantum yield (PLQY) of tin-based perovskites seriously hamper their practical application.
Liang Li, Shanghai Jiao Tong University, China, and colleagues have developed a simple strategy to synthesize highly efficient and stable all-inorganic lead-free Cs4SnBr6–SnF2 perovskites with SnF2 as the tin(II) source. The team used SnF2, CsBr, and NH4Br as precursors to prepare the desired perovskites by wet ball milling with ultrapure water.
The introduction of SnF2 suppresses the oxidation of Sn2+ during the synthesis of the perovskite, and the Sn–F bonds formed improve its stability. The Cs4SnBr6–SnF2 perovskite achieved a significant boost in PLQY from 2.8 % to 62.8 % compared with SnBr2-derived Cs4SnBr6 crystals. The SnF2-derived Cs4SnBr6 demonstrated high stability against oxygen, moisture, and light irradiation over the course of 1,200 hours. Using the perovskite as a green-light emitter, a white light-emitting diode (WLED) device was constructed with a high color rendering index (CRI) value of 96 % and a long-term operational stability of 1,000 hours.
- Stable Lead‐free Tin Halide Perovskite with Operational Stability >1200 h by Suppressing Tin(II) Oxidation,
Qinggang Zhang, Shiqiang Liu, Mengda He, Weilin Zheng, Qun Wan, Mingming Liu, Xinrong Liao, Wenji Zhan, Changwei Yuan, Jinyu Liu, Haijiao Xie, Xiaojun Guo, Long Kong, Liang Li,
Angew. Chem. Int. Ed. 2022.