Hydrothermal Synthesis and Ethanol-Sensing Properties of MoO_3 Nanobelts

摘要

Uniform M0O_3 nanobelts were synthesized through a fast and simple hydrothermal route without any other agents. The hydrothermal reaction was performed at 180 °C for 12 h using a HNO_3 aqueous solution as the solvent. The phases and microstructures were characterized using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results indicated that the sample obtained was an orthorhombic MoO_3 phase, and had a belt-like morphology with lengths of 5-10 μm and apparent widths of about 220 nm. The M0O_3 nanobelts obtained were used as the sensing materials to fabricate chemical sensors for detection of some volatile organic compounds (VOCs) (including ethanol, methanol, isopropanol, acetone, methanal, and benzene). The gas-sensing results indicated that the sensor of the (α-MoO_3 nanobelts has enhanced ethanol-sensing performance, e.g., with the highest sensitivity of S_r =144 for 500 ppm ethanol vapor operating at 300 °C.