Abstract：Pseudo-single crystal WO3 nanosheets photocatalyst was prepared by regulating the reaction temperatures, pH and the ratios of precursors during the hydrothermal processes, and the morphologies, crystalline phases, compositions and charge carrier separation performance were characterized by XRD, SEM, TEM, XPS, UV-vis and photocurrent density test. The photocatalytic activity of WO3 nanosheets for Rhodamine B degradation was studied under visible light irradiation. The results showed that monoclinic WO3 nanosheets were obtained with thickness of ~10nm and side length of 300~500nm, moreover, the nanosheets were proved with continuous lattice structures, higher energy band structure and improved charge carrier separation property. Results of the photocatalytic experiments showed that the degradation process of Rhodamine B by WO3 nanosheets followed first-order kinetic equation and the reaction rate constant was 2.91h-1, which was 5.2 times higher than that of WO3 nanoparticles (0.56h-1). It was speculated that the better catalytic activity of WO3 nanosheets was due to the higher charge carrier separation efficiency. Moreover, the experiment with scavengers under visible light irradiation proved that ·OH and ·O2- were both active free radicals in the process of pollutant degradation catalyzed by WO3 nanosheets. The cycling test proved that the photocatalyst possessed good stability.
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