Study on the Feasibility of Halide Perovskite Material based Gas Sensor for NO2 and NH3 Detection in Environmental Monitoring Applications

The identification of toxic gases, including ammonia (NH₃) and nitrogen dioxide (NO₂), at room temperature (RT) is essential for environmental monitoring and public health. Recently, halide perovskites (HP) have surfaced as intriguing candidates for gas sensing applications, attributed to their adjustable optoelectronic characteristics and robust interactions with gases. This research conducts a feasibility study of HP (MAPbCl₃, CsPbCl₃, and FAPbCl₃)-based gas sensor for the detection of NH₃ and NO₂ utilizing COMSOL Multiphysics. The sensor architecture comprises of a HP sensing layer, interdigitated gold electrodes, a ruthenium dioxide heating element, and an alumina substrate. It is observed that MAPbCl₃-built gas sensor exhibited exceptional performance, achieving sensitivities of 0.232 ppm^-1 for NO₂ and 0.2187 ppm^-1 for NH₃, alongside low limits of detection of 1 ppm and 3 ppm, respectively. Furthermore, it has demonstrated exceptional selectivity against a collection of various interfering gases and rapid response/recovery times (1.4 s/0.7 s for NO₂ and 1.5 s/0.8 s for NH₃). These augmented sensing characteristics can be accredited to the high lattice polarity and strong hydrogen bonding in MAPbCl₃, which promotes efficient charge transfer during redox reactions. The findings indicate that MAPbCl₃ is an auspicious candidate for low-power, high-performance toxic gas sensors functioning at RT.