High performance In2(MoO4)3@In2O3 nanocomposites gas sensor with long-term stability

Metal oxide semiconductor (MOSC) sensors based on nanocrystalline MoO3, In2O3, and their composites are considered to be very sensitive to detect low concentrations of ethanol, ozone, hydrogen, formaldehyde, and nitrogen dioxide. Here, we firstly introduced In2(MoO4)3 phase, which has excellent negative thermal expansion and high electric conductivity properties, into In2(MoO4)3@In2O3 crystalline nanocomposites. The gas-sensing performance of the In2(MoO4)3@In2O3 nanocomposites was studied upon exposure to the ethanol gas with different concentration from 5 to 300 ppm at the optimum temperature (300 °C). What's more, the device possesses ultra-high response of 110 and selectivity to ethanol. Particularly, it can effectively work in high humidity (RH = 80%) with super long-term stability of as long as 90 days, compared with the pristine In2O3 sensor and previous reports. The presented novel In2(MoO4)3@In2O3 sensor offers great opportunities for future ethanol detection under harsh conditions.