Significant improvement of ethanol sensitivity at low temperature for ZnSnO3 nano-particles: Co-decoration of nano-TiO2/CeO2 and increase of UV intensity

Abstract

Amorphous ZnSnO3 nanosphere particles were prepared based on the dehydration of their ZnSn(OH)6 precursors, which were synthesized by co-precipitation method with the presence of dimethylacetamide (DMAC) as organic functional reagent. The ZnSnO3 sample, originating from its ZnSn(OH)6 precursor with 9 wt% DMAC, has a high gas response of 320–500 ppm ethanol at 260 °C. After decoration of 12.5 wt% nano-TiO2, the above ZnSnO3 sample under 365 nm UV illumination (420 lx) obtains a gas response of 139–500 ppm ethanol at a low temperature of 80 °C. When the aforementioned TiO2@ZnSnO3 nanocomposite was alternatively illuminated by 385 nm UV illumination (468 lx), its ethanol response at the same concentration is as high as 223 at 120 °C. Furthermore, under 385 nm UV illumination, the further decoration of 1.0 wt% nano-CeO2 not only significantly improves the ethanol response of the above nano-TiO2@ZnSnO3 nanocomposite from 223 to 603, but also enables its operating temperature reduced from 120 to 100 °C. Possible reasons on the above experimental results were discussed.