Organic small molecule-assisted synthesis of high active TiO2 rod-like mesocrystals

Mesocrystals have received considerable attentions due to their novel structure, property and nonclassical crystallization process. In the present work, rod-like TiO2 (A) mesocrystals with high specific surface area and excellent photocatalytic activity have been synthesized through a facile and mild solvothermal route. The mesocrystal products are believed to be formed through an oriented-attachment formation mechanism. Based on a series of contrast experiments, the oriented attachment of TiO2 nanoparticles is found to be carried out under the synergism of hydrophobic bonds, π–π interactions and “mixed-esters-templates”. Also the growth of the crystal facet of anatase is found to be affected by the π–π interaction. The present study not only opens new avenues for rationally designing TiO2 mesocrystal materials with ideal hierarchy and controllable sizes, but also offers a promising opportunity to understand the formation process of these unique porous-crystalline superstructures.