Mesocrystals, which are assemblies of crystallographically oriented nanocrystals, have received increasing attention due to their unique properties such as high crystallinity, high porosity, oriented subunit alignment, and similarity to highly sophisticated biominerals. However, the controlled synthesis of TiO 2 mesocrystals has not been realized until recently, probably because of the difficulty in accurately controlling the reaction processes that produce TiO 2 crystals. In this review, recent advances in the synthesis and applications of TiO 2 mesocrystals are summarized with particular attention paid to the mechanisms of their formation. Three typical pathways for the preparation of TiO 2 mesocrystals are discussed, namely topotactic transformation, direct synthesis in solution, and growth on supports. The potential applications of TiO 2 mesocrystals in lithium ion batteries, photocatalysis, enzyme immobilization, and antireflection materials are also described.
The design and fabrication of nanostructures based on titanium dioxide (TiO 2 ) have attracted much attention because of their low cost, non-toxicity, stability, and potential applications in industry and technology. Recently, one-dimensional (1D) structured titanates have been used as titanium source to prepare TiO 2 nanostructures with various crystalline phases, shapes, sizes, exposed facets, and hierarchical structures. Among the synthetic strategies, hydrothermal method is a facile route to controllable preparation of well-crystalline TiO 2 in one step. Herein, we review our recent progress in transferring 1D titanates into TiO 2 nanostructures through hydrothermal method, including the transformation mechanism and applications.
