Fabrication of {010} facet dominant BiTaO₄ single-crystal nanoplates for efficient photocatalytic performance

The facets of nano-photocatalysts play an important role in their photocatalytic activity. Here, we prepared {010} facet dominant BiTaO₄ single-crystal nanoplates, which can both split water into H₂ and decompose organic dyes into non-toxic small molecules. UV-vis DRS, XPS valence band and Mott-Schottky measurements and DFT calculations demonstrated that the up-shift of the conduction band minimum significantly increased the reduction ability of photogenerated electrons, thus leading to highly efficient photocatalytic performance. Typical bulk BiTaO₄ does not have any water splitting capability and shows poor photodegradation activity. However, the {010} facet dominant BiTaO₄ single-crystal nanoplates realize the H₂ evolution of BiTaO₄ and improve the photodegradation activity 52 times via conduction band minimum up-shift. The understanding of the facet effect on photocatalysis will provide valuable instructions for the design of other photocatalysts.