h i g h l i g h t s• A series of tungsten-titaniumcocontained SBA15 composites were fabricated by a simple synthetic route.• These samples showed enhanced catalytic performance in comparison to those comprising bare tungsten or titanium component.• The enhancement of photocatalytic behavior under visible-light irradiation was discussed. t r a c tA 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, WO 3 /TiO 2 , and N-TiO 2 , respectively. The enhancement of photocatalytic performance was mainly attributed to the well-matched band structures of both components and strengthened visiblelight adsorption ability, originating from the combination of titania with highly acidic WO 3 in SBA15 matrix with large specific surface areas. Active radical species were detected by trapping experiments and a possible photocatalytic mechanism was thus proposed.

a b s t r a c tA series of tungsten-containing mesoporous SBA15 with different tungsten contents were prepared through a direct co-condensation sol-gel method and then analyzed by various techniques. XRD patterns revealed that the original mesoporous morphology was maintained after introducing tungsten species and forms of tungsten species were changed from incorporated tungsten to isolated tungsten species or low oligomeric tungsten oxide species, and finally to crystalline WO 3 with the increase of tungsten precursor content, which were also proven by HRTEM images, UV-Vis DRS, and FT-IR spectra. The W-SBA15 samples exhibited satisfactory photocatalytic performance toward degradation of dye Rhodamine B (RhB) and 2,4-dichlorophenol (2,4-DCP). In particular, the best candidate, sample 10%W-SBA15 showed an apparent reaction rate constant for RhB that was nearly 10 times as high as that of bulk WO 3 . The enhancement of photocatalytic capability was attributed to the mesoporous morphology with enlarged surface areas, negatively charged surface, and favorable tungsten forms such as incorporated tungsten, isolated tungsten or low oligomeric tungsten oxide species. In addition, active radicals trapping experiments and DMPO spin-trapping ESR spectra indicated that photogenerated holes were major oxidative species during photocatalysis.

h i g h l i g h t s• W-Ti-SBA15 composites with low TiO 2 /SiO 2 mass ratios and their Agcontained analogs were fabricated.• These composites showed enhanced photocatalytic performance in comparison to those with high TiO 2 /SiO 2 mass ratios.• Photocatalysis mechanism of these Ag-W-Ti-SBA15 plasmonic composites was proposed. t r a c tA group of mesoporous WO 3 -TiO 2 -contained SBA15 composites (W-Ti-SBA15) and their Ag-contained plasmonic analogs were fabricated and then systematically characterized by a collection of analytical techniques. Original mesoporous structures with highly ordered channels were well-maintained and WO 3 -TiO 2 could form spherical clusters that were gradually reduced in size accompanying with the decrease of TiO 2 /SiO 2 mass ratios. Deposited Ag species were confirmed as zero-valence Ag by X-ray photoelectron spectroscopy analysis and exerted almost no effect on the morphology, microstructure, and textural but optical property, by which the visible-light harvesting ability of composites was remarkably strengthened owing to the localized surface plasmonic resonance (LSPR) induced by the metallic Ag. Under visible-light irradiation, W-Ti-SBA15 composites showed satisfactory photocatalytic performance that could be further enhanced by using their Ag-contained ternary plasmonic analogs. The enhancement of photocatalytic efficiency was mainly attributed to the favorable mesoporous morphology, the suitable band alignment, and the LSPR effect. Eventually, a possible photocatalysis mechanism was primarily proposed on the base of reactive radical species trapping experiments.