Fabrication of ZnO nanoparticles based sensitive methanol sensor and efficient photocatalyst

ZnO nanoparticles (NPs) were prepared by hydrothermal treatment with starting materials (zinc chloride and urea) in the presence of ammonium hydroxide and characterized by powder X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and UV–vis spectroscopy. The synthesized nanoparticles are crystalline with wurtzite hexagonal phase having average particle size in the range of 80–130 nm. Photocatalytic activity of the prepared ZnO NPs was evaluated by the degradation of methylene blue and almost complete degradation (91.0%) takes place within 85 min of irradiation time. Prepared ZnO nanostructures possessed high photocatalytic activity when compared with TiO2-UV100. Additionally, the sensing properties of the ZnO films were investigated for various concentrations of methanol in liquid phase by simple I–V technique at room conditions. It was observed that ZnO thin film exhibits good sensitivity (0.9554 μA cm−2 mM−1) towards detection of methanol at room conditions.