Preparation, characterization and photocatalytic activity of three-dimensionally ordered mesoporous/macroporous TiO₂ microspheres

Three-dimensionally ordered mesoporous/macroporous TiO₂ microspheres were synthesized through sol-gel assisted template method using the self-made poly-(methyl methacrylate) (PMMA) microspheres as hard template, and two kinds of titanium source, such as titanium isopropoxide and tetrabutyl titanate, were used as metal precursor. On the basis of characterization results of XRD, SEM, TEM, UV-vis DRS and N₂ adsorption/desorption, the morphology, optical absorption, surface area, pore distribution and catalytic activity of the as-prepared samples were systemically investigated. The characterization results reveal that the as-prepared TiO₂ samples possess uniform microsphere structure, large surface area and high crystallinity. The obtained mesoporous/macroporous microspheres show the enhanced photocatalytic activity, which is found to be 90% degradation efficiency of RhB with 10 mg/L concentration under UV light irradiation for 120 min.