Synthesis and adsorption-photodecomposition properties of mesoporous SiO2–TiO2/WO3 composite

Gaseous volatile organic pollutants may be removed from the environment through photocatalysts combined with adsorbents. Herein, a mesoporous SiO2–TiO2/WO3 composite was fabricated by the sol–gel method in order to remove acetaldehyde in the gas phase. TiO2 and WO3 were well-dispersed in the SiO2 matrix. The adsorption-photodecomposition properties of mesoporous SiO2–TiO2/WO3 were evaluated through a three-step kinetic analysis, including direct-decomposition, adsorption, and adsorption-decomposition. The composition of WO3 in the SiO2–TiO2 increased the acidity and improved the affinity between the photocatalyst and acetaldehyde. This effectively enhanced the initial removal rate of acetaldehyde. The atomization of WO3 further improved the affinity between the photocatalyst and acetaldehyde and enhancing the photodecomposition rate constant.