Environment friendly lead-free Cs3Sb2Br9 perovskite: Wide measure range, high sensitivity, and rapid sensing response for high-performance humidity sensor

Abstract

Due to the superiority of easy manufacture, low cost, coupled with super optoelectronic attributes, the metal halide perovskites have appeared as an emerging class of semiconductors owning their considerable potential for assorted utilization in humidity sensors. Nevertheless, the toxicity problem along with inherent instability of lead (Pb) halide perovskites is grimly impeding the large-scale manufacturing as well as commercialization. Herein, lead-free Cs3Sb2Br9 perovskites were successfully synthesized using a modified ligand-assisted reprecipitation approach and the humidity sensing properties relevant for humidity sensor applications were investigated. The as-fabricated Cs3Sb2Br9 humidity sensors display a super-high impedance variation of more than 105, and the testing range can be extended to a very low humidity (2% relative humidity, RH). The value of hysteresis is as low as 2.9%, and the response/recovery time is discovered to reach ∼0.9/3 s from 11% to 95% RH, which owns a large potential in the detection of the real-time moisture. Moreover, the Cs3Sb2Br9 humidity sensor boasts good reversibility and a remarkable level of stability. Our results demonstrate the potential for lead-free Cs3Sb2Br9 perovskites in a real-time and high-performance humidity sensor.