Surface engineering induced superstructure TaO mesocrystals for enhanced visible light photocatalytic antibiotic degradation.

Mesocrystals are types of fascinating multifunctional materials in fabricating rapid charge transport pathways, and surface engineering could be considered as a significant influencing factor in boosting charge separation for efficient photocatalytic application. In this work, surface engineered TaO mesocrystals were synthesized by facile alkali treatment strategy for enhanced visible light photocatalytic tetracycline degradation. The highly enhanced photocatalytic activity could be attributed to the highly increased surface areas and surface hydroxyl groups to compare with those of commercial TaO and pristine TaO mesocrystals, which could provide more surface reactive sites and high electron density center for trapping photo-generated holes. Besides, possible tetracycline transformation pathways over surface engineered TaO mesocrystals and visible light photocatalytic mechanism were also proposed in this work. Current work also provides a facile strategy for regulating surface property of ultrawide bandgaps semiconductors for enhanced visible light photocatalytic performance.