Designed fabrication of anatase mesocrystals constructed from crystallographically oriented nanocrystals for improved photocatalytic activity

Abstract

In this article, we report a new route to synthesize octahedral anatase mesocrystals (MCs), polycrystals (PCs) and single crystals (SCs) in the TiCl₄–CH₃COOH system just by tuning the reaction time and Ti-source concentration. Owing to the unique structures constructed from crystallographically oriented nanocrystals, MCs offer larger specific surface area than SCs and more effective electron transport compared with PCs. As anticipated, MCs show the highest photocatalytic activity in the degradation of methylene blue. MCs also demonstrate excellent cycle stability and renewable capability, and the photocatalytic efficiency still remains up to 90% even after five cycles. The designed fabrication of mesocrystals provides an attractive and effective route for improving the performances of semiconductor photocatalysts.