In this work, a simple solvothermal method was used for the synthesis of cuboid WO3 crystals without any surface active agent. The calcined WO3 was characterized using field emission scanning electron microscopy (FESEM), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The results indicate that the sample is composed of cuboid nanobulks. The gas sensing property of a sensor based on the cuboid WO3 was also investigated. It is found that the sensor has a high response to low concentration NO2 at low operation temperature, so the cuboid nanobulks might have a potential application in the fabrication of highly sensitive and low power consumption NO2 gas sensors.
