Highly sensitive ethanol sensors based on {100}-bounded In2O3 nanocrystals due to face contact

Abstract

The authors report the fabrication and characterization of ethanol sensors with extremely high sensitivity using ${\mathrm{In}}_2{\mathrm{O}}_3$ nanocrystals bounded by {100} facets as the sensing materials. The sensitivity of the sensors is about $10\text{to}1\mathrm{ppm}$ ethanol, and increases nearly linearly up to about 200 as the ethanol concentration is raised to $100\mathrm{ppm}$ . In the sensing film, the nanocrystals contact each other mainly through face contacts, most of which contribute to the gas sensing. This is the basis for the highly sensitive ethanol sensing.