Versatile Gas Sensing at Room Temperature: Facile Fabrication of a PANI-PB-ZnO Hybrid Nanocomposite for Detecting Ammonia, Acetone, and Ethanol

This study presents a gas sensor utilizing a metal–organic framework composed of nanostructured zinc oxide and polyaniline, exhibiting effective detection of acetone, ammonia, and ethanol gases under ambient room temperature conditions. It includes a comprehensive analysis of the structural characteristics and gas sensing capabilities of a PANI-PB-ZnO nanocomposite, elucidating the intricate interplay of its components and its exceptional responsiveness to ammonia gas. Structural analysis of the PANI-PB-ZnO nanocomposite reveals a semicrystalline structure with an average particle size of 27 nm. The composite morphology shows polyaniline nanoparticles adorned with zinc oxide-coated Prussian blue nanocubes. The gas sensing properties of the PANI-PB-ZnO sensor, modified with a protective layer, were investigated by exposing it to different concentrations (0–500 ppm) of volatile gas analytes at room temperature. The experimental findings showcased the PANI-PB-ZnO sensor’s remarkable response and selectivity towards ammonia gas. The enhanced sensitivity to ammonia gas can be attributed to the synergistic/complementary effects of PANI, PB, and ZnO nanoparticles and the interactions at the p–n heterojunction.