Bi2WO6 Thin Nanoplates Decorated with Pt Nanoparticles Possessing Enhanced Visible-Light-Driven Photocatalytic Performance for Rhodamine B Degradation

Thin Bi2WO6 nanoplates decorated with 1, 5 and 10 wt % Pt nanoparticles have been successfully prepared by photoreduction deposition method. X-ray diffraction patterns of the Pt/Bi2WO6 nanocomposites show only orthorhombic Bi2WO6 structure because the loaded Pt content is too low to be detected and the Pt nanoparticles are very tiny. Upon characterization the Pt/Bi2WO6 nanocomposites by scanning electron microscopy and transmission electron microscopy, the Pt nanoparticles with 8-10 nm in size have been supported on the surface of thin Bi2WO6 nanoplates to form the Schottky interface. Diffuse reflectance spectroscopy spectrum of 10 wt % Pt/Bi2WO6 nanocomposites is in the visible light region due to the surface plasmon resonance effect of Pt nanoparticles. Rhodamine B (RhB) solution was used to probe the photocatalytic activity of the as-prepared Bi2WO6 and Pt/Bi2WO6 samples induced by visible radiation. The Pt/Bi2WO6 nanocomposites show the excellent RhB degradation due to the synergy of Pt nanoparticles loaded on top of thin Bi2WO6 nanoplates. The RhB degradation photocatalyzed by heterostructure 10 wt % Pt/Bi2WO6 nanocomposites is the highest of 98.70%. Photostability and active radical trapping test for RhB degradation over heterostructure 10 wt % Pt/Bi2WO6 nanocomposites have been investigated. Photocatalytic mechanism of Pt/Bi2WO6 nanocomposites is explained according to the experimental results.