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

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 degrees 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 degrees 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 degrees 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 degrees C. Possible reasons on the above experimental results were discussed.