High-Performance Room-Temperature Gas Sensors Based on CH3NH3PbI3 : ZnS Nanostructures

A highly sensitive methyl ammonia lead iodide (CH3NH3PbI3) with perovskite structure was syntheses to sense harmful, hazardous, and polluting gases in the environment. The pure and doped samples of methyl ammonia lead iodide (MAPI) were prepared by chemical distillation method and deposition by drop-casting method. To improve the sensitivity, response time and to change the structural properties of the pure MAPI sample, zinc sulfide was added in three different molar concentrations (1 : 0.01 M, 1 : 0.025 M, 1 : 0.05 M). The electrical sensitivity were measure of those doped with zinc sulfide for NH3 and alcohol vapor gases. The structural properties are observed through X-ray diffraction (XRD) spectra show a minor displacement of the diffraction peaks toward higher 2θ values. The field emission scan electron microscope (FESEM) appeared like wires or rods and had an average diameter of roughly 49 nm for pure MAPI and 46 nm for doped ones. The MAPI:ZnS 1:0.01M had a higher sensitivity of approximately 700% at room temperature, while the maximum sensitivity to alcohol gas reached 443% for the same sample.