Template-free Synthesis of Hierarchical Titania Microspheres with Controlled Morphology Evolution

Template-free synthesis of hierarchical Ti〇_2 microspheres with controlled morphology evolution was achieved by simply varying the molar ratio of HC1/TTIP under solvothermal reaction in 1,4-dioxane. By syste-mati-cally controlling the HC1/TTIP molar ratio from 0 (or 0.7,_(0.9)) to 1.8,3.6 and 5.7,nanoparticulate microspheres, microspheres decorated with nanorods, nanorod cauliflowers, and nanorod sea urchin structures were synthesized respectively. The mechanism for the morphology evolution was discussed. The photocatalytic performance of the TiO_2 microspheres with different morphologies for water splitting was investigated. It was found that the microspheres decorated with nanorods exhibited the best performance due to the coexistence of anatase and rutile phases.