Monoclinic WO3 was prepared by a hydrothermal reaction of PbWO4 in the presence of HNO3. WO3 rectangular nanoplates with a side length of 50-150 nm and a thickness of about 25 nm were obtained at 4 M HNO3 solution. And the single crystal nature was confirmed by the selected area electron diffraction. Whereas WO3 hierarchical flower-like assemblies with 3-5 mu m in diameter were self-organized by nanoplates in the presence of 15 M HNO3 solution. Compared with commercial WO3 particles, our products showed an enhancement of photocatalytic properties for the degradation of rhodamine B under visible light irradiation. (C) 2013 Elsevier Ltd. All rights reserved.