Enhanced photocatalytic properties of TiO2-loaded porous silica with hierarchical macroporous and mesoporous architectures in water purification

Abstract

Porous silica with hierarchical macroporous and mesoporous architectures (MacroMeso-SiO₂) was prepared by a solvent evaporation method using a precursor solution for the synthesis of mesoporous silica (Meso-SiO₂) and poly(methyl methacrylate) (PMMA) colloidal crystals as a hard template and used as an advanced support for TiO₂ photocatalysts. The porous structure and state of TiO₂ were investigated by various characterisation techniques. Reflecting the structure of aligned PMMA microspheres, MacroMeso-SiO₂ has a uniform and hierarchical macroporous structure with interconnecting networks even after the loading of TiO₂ particles. Based on its advantageous porous structure, TiO₂-loaded MacroMeso-SiO₂ exhibited specific characteristics, i.e., the easy transportation of relatively large molecules and unique adsorption properties to condense organic compounds, and enhanced photocatalytic properties in the degradation of organic compounds in water as compared to TiO₂-loaded Meso-SiO₂ under UV light irradiation.