Zinc stannate microcubes with an integrated microheater for low-temperature NO2 detection

Abstract

This paper reports a facile technique to construct an oxide nanostructured film on a low-power microheater sensor platform to detect NO₂ gas with high sensitivity and selectivity at a low temperature. Microcube-shaped zinc stannate (ZnSnO₃) nanostructures prepared through a co-precipitation method were used to detect NO₂ down to 85 ppb at 110 °C with a fast response and recovery time. Specifically, a 192% response in the resistance change was measured for 5 ppm NO₂ gas, with a response time of 3.36 mins, excellent reproducibility, long-term stability, and high selectivity. The good gas-sensing performance of the ZnSnO₃ microcubes is due to their porous surface, which provides a large surface area and suitable absorption–desorption processes. The versatility of the ZnSnO₃ nanostructures may be further exploited with various sensing units on a single chip towards the development of arrays, as in electronic noses.