Enhanced visible-light-driven photocatalytic performance of mesoporous W-Ti-SBA-15 prepared through a facile hydrothermal route

摘要

A facile and one-step hydrothermal procedure was adopted to fabricate a series of W-Ti-SBA15 composites (WTS). These as-prepared composites were systematically characterized by a collection of analytic and spectroscopic techniques. It was found that dual phases of titanium and tungsten species coexisted in mesoporous structures of p6 mm hexagonal symmetry. In addition, these composites were visible-light responsive and exhibited enhanced photocatalytic capability toward degradation of Rhodamine B (RhB) and 2,4-dichlorophenol (2,4-DCP) upon visible-light irradiation in comparison to samples containing single component of titanium or tungsten species. Specifically, the best candidate, sample 8%WTS0.7, had the largest apparent reaction rate constant that was nearly 1.2, 2.1, 2.2, and 5.7 times as high as those of 8%WS, TS0.7, WO3/TiO2, and N-TiO2, respectively. The enhancement of photocatalytic performance was mainly attributed to the well-matched band structures of both components and strengthened visible light adsorption ability, originating from the combination of titania with highly acidic WO3 in SBA15 matrix with large specific surface areas. Active radical species were detected by trapping experiments and a possible photocatalytic mechanism was thus proposed. (C) 2016 Elsevier B.V. All rights reserved.