Investigation of Mixed-Phase WS2 Nanomaterials for Ammonia Gas Sensing

In this article, WS2 nanomaterials with different phases are Synthesized, and their gas-sensitive properties of ammonia are analyzed systematically. First, hydrothermal method and liquid phase method were used to prepared the different phase material. Moreover, the nanostructure and morphology are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). On the basis of result of the XRD, the difference between the peaks indicates different crystal structure. And SEM show the calcination temperature affects the morphology, and the same materials with different morphologies have similar optimum working temperature. Finally, the gas sensing performance of different WS2 sensor is investigated in different concentration of ammonia gas at optimal temperature. The results indicate that the mixed-phase exhibited a low detection limit, excellent selectivity and superb repeatability compared with 3R phase.