High performance and low detection limit isopropanol gas sensor based on 3D ZnSnO3 nanocubes co-catalyzed by Au nanoparticles and ZrO2

In this paper, Au nanoparticles (AuNPs) loaded ZrO2/ZnSnO3 nanocubes are prepared through hydrothermal route and chemical reduction method. The crystal structure, morphology, element distribution, chemical composition, specific surface area and pore size of ZrO2/ZnSnO3 nanocubes are described with XRD, TEM, XPS and BET. Interestingly, the incorporation of Zr ions induces the fragmentation of the edge of ZnSnO3 nanocubes, which enhance specific surface area of ZrO2/ZnSnO3 nanocubes. The response of ZnSnO3 materials for isopropanol is increased through doping ZrO2 and modifying AuNPs. The 1.5 at% AuNPs-loaded 5 at% ZrO2/ZnSnO3 nanocubes presents a higher response to 100 ppm isopropanol with a fast response/recovery time (3/4 s) at the operating temperature of 260℃. And the generation of ZnSnO3, ZrO2 and AuNPs heterojunctions contributes to raise the isopropanol response. In addition, the catalysis of ZrO2 and AuNPs also can increase their reaction speed between absorbed oxygen and isopropanol molecules. This research results provide a new scheme for the development of isopropanol sensor.