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.