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

Abstract

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.

Study of the structure and characteristics of mesoporous TiO2 photocatalyst, and evaluation of its factors on gaseous formaldehyde removal by the analysis of ANOVA and S/N ratio

“…The high concentration of Ti formed a different framework from that of the incorporated silica species. 43 Thereafter, the decreased number of Si sites around the P123 surfactant and the shorter hydrolysis time of Ti resulted in a three-dimensional porous structure after the condensation process. 27 …”

“…The Ti2p 3/2 or Ti2p 1/2 peak shied to a lower binding energy by approximately 2 eV compared to the anatase phase of Ti 4+ . 32, 43 Gao et al 48 indicated that the blueshi might be associated with the Ti-O-Si bonds, resulting in a more positive charge on Ti, a less negative charge on O, and more negative charge on Si. With increasing Ti content, the intensity of the peak increased as the Ti/Si ratio improved.…”

“…The band at 527.9 eV corresponded to the lattice oxygen of the Ti-O-Ti bond. 25,28,43,51 As the Ti/Si ratio increased, the intensity of the Ti-O-Ti bond became stronger for TR (50). The O1s peak at 530.1 eV was deconvoluted into three peaks.…”

Fabrication, characterization, and visible-light photocatalytic performance of ternary plasmonic composites

“…In a previous study, the synthesis and photocatalytic assessment of mesoporous W-Ti-SBA15 composites were investigated, and these heterojunction-structured composites showed enhanced photocatalytic efficiency in comparison to single-component samples [29]. However, the photocatalytic performance was not as that good as we had expected, mainly attributing to the serious aggregation of TiO 2 particles since the excess amount of titanium precursor was added during synthesis.…”

“…The synthetic procedure was similar to the previous study except that the amount of titanium and tungsten precursors was greatly reduced [29]. A series of W-Ti-SBA15 mesoporous composites were prepared and nominated as 5%WTSx, where 5% and x were defined as theoretical mass ratios of formed WO 3 /TiO 2 and TiO 2 /SiO 2 , respectively.…”