Morphology tuned ZnS nanostructures for hydrogen gas sensing

In this paper we present the effect of dimensionality of ZnS nanostructures on hydrogen gas sensing characteristics. Vapor Liquid Solid growth mode was employed to synthesize ZnS nanostructures with different dimensions by controlling the growth parameters, i.e., variation in the substrate temperature and the carrier gas flow rate. The growth was explained by using the chemical tension model and the saturation conditions were determined for each growth. X-ray diffraction and scanning electron microscopy were used to determine the phase, shape, size and density of the nanostructures. Optical properties of nanostructures also confirmed the presence of different phases of ZnS. A variety of these nanostructures were tested for hydrogen gas sensing. The rapid response time was obtained for nanowires in few hundred millisecond’s range with a sensitivity of 8, which was due to its high aspect ratio as compared to the other nanostructures.