Chen, HongjunZhang, Meng YaoFu, XiaoFusco, ZelioBo, RenhengXing, BobinNguyen, HieuBarugkin, ChogZheng, JianghuiLau, Cho Fair JonathanHuang, ShujuanHo-Baillie, AnitaCatchpole, KylieTricoli, Antonio2023-08-041463-9076http://hdl.handle.net/1885/294795Halide perovskite materials are excellent light harvesters that have generated enormous interest for photovoltaic technology and an increasing number of other optoelectronic applications. Very recently, their use for miniaturized chemical sensors has shown a promising room-temperature response. Here, we present some insights on the use of CsPbBr2I (CPBI) perovskites for self-powered room-temperature sensing of several environmentally and medically relevant compounds demonstrating rapid detection of down to concentrations of 1 ppm. Notably, the photocurrent of these self-powered CPBI-based devices increases under exposure to both reducing (e.g. acetone, propane) and oxidizing (e.g. NO2, O2) gas molecules and decreases rapidly upon reverting to an inert atmosphere. In situ photoluminescence (PL) analysis of the CPBI during exposure to oxidizing molecules reveals a strongly increased PL intensity and longer lifetime indicating a prevalent role of CPBI trap states in the sensing mechanism. These findings provide new insights for the engineering of perovskite-based materials for their future chemical sensing applicationsA. T. gratefully acknowledges the support of Australian Research Council (ARC) DP150101939, ARC DE160100569, and Westpac 2016 Research Fellowship. M. Z. S. H and A. H.-B acknowledge the support of the Australian government via financial support from the ARC through the DP160102955 program and the Australian Renewable Energy Agency. H. T. N. acknowledges the support of an Australian Center of Advanced Photovoltaics Fellowship. K. R. C. acknowledges the support of an ARC Future Fellowship. Financial support from ARC through DP160102955 is also acknowledged.application/pdfen-AUThis journal is © the Owner Societies 2019201910.1039/c9cp03059j2022-06-26