Facile synthesis of Cs3Bi2Br9 perovskite nanoplates with low-polarity antisolvents for photodetection applications

Lead-free metal-halide perovskites have garnered tremendous attention in recent times for their excellent properties, such as high light absorption coefficient and high charge-carrier diffusion length. Herein, we report the synthesis and investigation of lead-free Cs3Bi2Br9 perovskite nanoplates for visible light photodetection applications. The Cs3Bi2Br9 nanoplates were synthesized by a facile reprecipitation method based on the selection of antisolvents. The synthesized nanoplates present phase-pure crystal quality and exhibit reduced trap states, resulting in a high on/off current ratio of ∼103 under illumination at a wavelength of 405 nm in ambient air. This study thus hints at new opportunities for stable and low-toxicity perovskite-based optoelectronic applications.