Studying of the structural and optical properties of lead halide perovskite and useing in detecting ammonia gas

This study shows that leads halide perovskites that have various cations and anions may be utilized to build highly selective and sensitive at room-temperature the gas ammonia (NH₃) gas sensors with visually responses. The first step is to apply a layer of Pbl₂ to the paper, followed by another layer of methylammonium iodide (CH₃NH₃I) or (MAI). This process resulted in the perovskite MAPI film. The study discovered that using two-step synthesis processes improves the stability of MAPI films. The solution is used to create paper sensors including components such as methylammonium lead iodide (CH₃NH₃PbI₃) or (MAPI). When MAPI is exposed to NH₃, its color changes from black to yellow. The proposed technique principally includes the breakdown of the halides perovskite into (Pb) halides by favored absorption of NH₃ molecules of gas. The XRD measurement shows formation of MAPI perovskite with small amouts of PbI₂, with 36–49 nm grain size as seen in SEM image.