Preparation, characterization and catalytic behavior of SnO2 supported Au catalysts for low-temperature CO oxidation

Abstract SnO 2 nanocrystals were synthesized by a precipitation process and then used as the support for Au/SnO 2 catalysts preparation via a deposition–precipitation method. The samples were characterized by means of X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM)/energy-dispersive X-ray spectra (EDS) and X-ray photoelectron spectroscopy (XPS). The influence of calcination temperature of SnO 2 support, calcination temperature of Au/SnO 2 catalysts and Au loading on the catalytic activity of Au/SnO 2 catalysts was investigated. The SnO 2 samples calcined at 573 and 673 K were found to be the suitable support materials for Au/SnO 2 catalysts. In all investigated Au/SnO 2 catalysts with different Au loading from 0.36 to 5.00 wt.%, the catalytic activity of the catalyst with 2.86 wt.% Au loading was the highest. The optimum calcination temperature of the Au/SnO 2 catalysts was 473 K. According to XRD, HRTEM and XPS, the catalytic activity of the Au/SnO 2 catalysts was related to the particle size of gold and tin oxide support, the fraction of metallic state Au and the degree of crystallinity of tin dioxide support.