Tuning the p-type conductivity of NiO for the room temperature formaldehyde detection

The present research synthesizes pure Nickel Oxide (NiO) nanostructures via a coprecipitation route with exceptional surface modification by temperature treatment. The morphological, structural, elemental and gas sensing tests of the prepared NiO were done carefully. The study unveils the sensing performances of various volatile organic compounds (VOCs), specifically for HCHO. Furthermore, gas sensor testing of prepared samples was carried out at room temperature (RT) and at different concentrations of the target gas. For 100 ppm of target gases, NiO (300 ℃), NiO (500 ℃), and NiO (700 ℃) gas sensors exhibited 83.43, 5616, and 196 gas responses, respectively, at RT. Hence, NiO nanoparticles at 500℃ sintering temperature-based HCHO sensor showed a significant response than other NiO sensors.