Improved gas sensing properties of silver-functionalized ZnSnO3 hollow nanocubes

摘要

Hollow ZnSnO3 nanocubes were successfully synthesized by a simple solvothermal strategy and then silver nanoparticles were decorated on the surface of ZnSnO3 by an effective deposition method. The morphology, microstructure, crystalline nature and the chemical compositions of the products were characterized by a variety of techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The prepared Ag-functionalized ZnSnO3 was found to be a novel porous hollow structure by characterization. This structure has a larger specific surface area and high gas permeability, thus allowing the material to make sufficient in contact with the analyte molecules. In order to further study the gas sensing performance of the samples, Ag-functionalized ZnSnO3 gas sensors were fabricated. The results show that Ag-functionalized ZnSnO3 nanocubes could enhance the gas sensing properties of ZnSnO3 to acetone. In particular, the Ag-functionalized ZnSnO3 with an atomic ratio of 0.6% realized a high gas response, ultrafast response/recovery speed, a low detection limit (1 ppm) and strong selectivity to acetone. The response of the Ag-functionalized ZnSnO3 sensor was 31.62-100 ppm, which was 3.18-times higher than that of the pristine ZnSnO3 hollow nanocubes. In addition, the formation mechanism of the hollow structure and the mechanism of Ag modification to improve the sensing performance of ZnSnO3 sensor were discussed.