Applied Catalysis B: Environmental, Vol.142, 119-128, 2013
Facile template free method for textural property modulation that enhances adsorption and photocatalytic activity of aperiodic titania supported silica materials
A series of aperiodic titania-silica photocatalysts were prepared in ethanolic solutions of co-solvents such as ethyl acetate (EtOAc), acetonitrile (ACN), acetone (ACT), and N,N'-dimethylformamide (DMF) using a combination of sol-gel chemistry and mild hydrothermal conditions. Extensive structural characterization emerged critical in demonstrating that the incorporation of such polar aprotic solvents is a viable approach for the enhancement and modulation of textural properties such as surface areas and pore sizes without the use of expensive templates. These studies revealed that the dark adsorption capacities of Rhodamine B (RhB) dye were dependent on the pore volume, and had minimal role on the photocatalytic degradation of the dye molecules. However, photocatalysts with large pore diameters exhibited improved initial degradation rates, suggesting that the sizes of the pores through which organics can diffuse in and out of the mesostructure are vital for their effective photocatalytic degradation under visible light irradiation. This work provides an insight into the use of facile preparation methods for the design of photocatalysts of desired porosities that are optimal for application in areas such as persistent organic pollutant remediation in waste water management. (c) 2013 Elsevier B.V. All rights reserved.