Photocatalytic degradation of rhodamine B by TiO2/SBA-15 nanocomposites

The TiO₂/SBA-15 composites with various titania contents were prepared by loading titania into the SBA-15 molecular sieves via a sol-gel method. The prepared TiO₂/SBA-15 composites were characterized by XRD, N₂-adsorption, and UV-vis techniques. It is shown that titania crystalline type is anatase phase. The BET surface area and pore volumes of the composites decrease with the increase of titania loading, while average crystal size of anatase phase particles increases with increasing titania loading. The photocatalytic degradation of rhodamine B was used as a probe reaction to evaluate the photoactivity of TiO₂/SBA-15 composites. Experimental results indicate that the degradation of rhodamine B over the composites followed first-order reaction kinetics, and the composites exhibited higher photoactivity. The photocatalytic activity of TiO₂/SBA-15 composites depend on the adsorption ability of the composites and the photocatalytic activity of titania loaded in SBA-15 molecular sieves.