title: Hierarchical TiO2 microspheres: synergetic effect of {001} and {101} facets for enhanced photocatalytic activity.
abstract: Well-faceted nanocrystals of anatase TiO(2) with specific reactive facets have attracted extraordinary research interest due to their many intrinsic shape-dependent properties. In this work, hierarchical TiO(2) microspheres consisting of anatase nanosheets or decahedrons were synthesized by means of a facile hydrothermal technique; meanwhile, the percentage of {001} facets can be tuned from 82 to 45%. Importantly, by investigating the photo-oxidation reactions for ˙OH radical generation and photoreduction reactions for hydrogen evolution, the TiO(2) microspheres consisting of nano-decahedrons with 45% {001} facets show superior photoreactivity (more than 4.8-times) compared to the nanosheets with 82% {001} facets. By analyzing the results of scanning electron microscopy (SEM), photoluminescence (PL) and first-principles density functional theory (DFT) calculations, a model of charge separation between the well-formed {001} and {101} facets is proposed, and the enhanced photocatalytic efficiency is largely attributed to the efficient separation of photogenerated charges among the crystal facets co-exposed.
authors.affiliation: State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China.
authors.forename: Zhaoke
authors.initials: Z
authors.lastname: Zheng
authors.forename: Baibiao
authors.initials: B
authors.lastname: Huang
authors.forename: Jibao
authors.initials: J
authors.lastname: Lu
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Qin
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Dai