Template-Assisted Synthesis of CsPbBr 3 Nanocrystals with a Humidity-Induced Fluorescent Response: Mechanism and Sensing Applications

作者：Pavel M. Talianov, Daria D. Mikushina, Sergey S. Rzhevskiy, Konstantin V. Arabuli, Лев Е. Зеленков, Soslan A. Khubezhov, Lev Logunov, Dmitry Gets, Oleksii O. Peltek, Mikhail V. Zyuzin, Sergey Makarov · 发表于：The Journal of Physical Chemistry Letters · 年份：2025 · DOI：10.1021/acs.jpclett.5c00151 · 被引用次数：4 · 研究领域：Perovskite Materials and Applications、2D Materials and Applications、Gas Sensing Nanomaterials and Sensors

Metal halide perovskites present a vast potential for the development of cutting-edge optoelectronic devices. However, their vulnerability to environmental factors, especially humidity, leads to widely acknowledged stability challenges. On the other hand, such a high sensitivity to water in the atmosphere is an opportunity for humidity sensing applications. In this study, we synthesize lead halide perovskite CsPbBr 3 nanocrystals within CaCO 3 templates with a porous structure (CsPbBr 3 @CaCO 3 ) and investigate the mechanisms underlying the fluorescence response to changes in relative humidity. The reversible transformation of CsPbBr 3 to CsPb 2 Br 5 leads to the removal of surface defects, which results in an increase in photoluminescence intensity, thereby enabling the determination of ambient relative humidity levels. Moreover, we investigated a mechanism of CsPbBr 3 degradation driven by CO 2 in humid environments underlying the perovskite transformations. As a proof of concept, we developed a fluorescence-based humidity sensor based on CsPbBr 3 @CaCO 3 with rapid response and recovery times, maintaining performance across multiple cycles.