Low-temperature synthesis of WO3 nanolamella and their sensing properties for xylene

Tungsten trioxides (WO3) are an important class of n-type semiconductor oxide materials with a wide bandgap. In this work, nanolamella of tungsten oxides have been successfully synthesized by a simple, facile and cost-effective route starting from Na2WO4 and subsequent calcination at 300 degrees C. The structure and morphology of the nanolamella were characterized by X-ray diffraction (XRD) scanning electron microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and photoluminescence (PL), respectively. The morphologies of the prepared products can be tailored by changing the calcination temperature. The obtained WO3 products were investigated as sensitive materials for the detection of xylene. On the basis of gas sensing tests, the sensor using WO3 nanolamella after annealing at 300 degrees C for 2 h exhibited better gas sensing properties. The maximum response reached 47 to 100 ppm of xylene at 280 degrees C. These results indicated that the gas sensors based on WO3 nanolamella express high and fast response and recovery characteristics to xylene, and the WO3 nanolamella are promising sensitive materials for xylene detecting.