Enhanced Photoactivity of Oxygen-Deficient Anatase TiO₂ Sheets with Dominant {001} Facets

Abstract

Constructing photocatalytically favorable surface structure in synthesizing photocatalysts plays an important role in enhancing the photocatalytic activity of semiconductor photocatalysts. In this report, oxygen-deficient anatase TiO 2 sheets with dominant {001} facets were synthesized via a facile one-pot hydrothermal route with solid metallic titanium diboride as precursor. In contrast to anatase TiO 2 sheets with dominant {001} facets free of oxygen deficiency and surface fluorine, anatase TiO 2 sheets with oxygen deficiency and surface fluorine are subject to obvious surface reconstruction as evidenced by two new Raman-active modes at 155 and 171 cm −1 and the weakened B 1g mode at 397 cm −1 . Further analysis based on X-ray photoelectron spectroscopy (XPS) spectra of Pt 4f and F 1s provided a clear evidence for the greatly strengthened interaction between Pt-loaded and TiO 2 matrix as a result of a special electron-transfer process on the reconstructed surface structure of TiO 2 with both oxygen deficiency and fluorine. Importantly, the reconstructed surface structure as well as the strengthened interaction between Pt-loaded and TiO 2 matrix can substantially enhance the hydrogen evolution rate from photocatalytic water splitting reactions.