Visible Light Active Pure Rutile TiO2 Photoanodes with 100% Exposed Pyramid-Shaped (111) Surfaces

Abstract

A pure rutile TiO2 photoanode with 100% exposed pyramid-shaped (111) surfaces has been directly synthesized on a fluorine-doped tin oxide (FTO) conducting substrate via a facile one-pot hydrothermal method. The resulting rutile TiO2 film on the FTO substrate possessed a film thickness of ca. 5 μm and showed good mechanical stability. After calcination at 450 °C for 2 h in argon (Ar), the fabricated rutile TiO2 films with 100% exposed pyramid-shaped (111) surfaces were used as photoanodes, exhibiting excellent visible light photoelectrocatalytic activity toward oxidation of water and organics. The excellent visible light activity of the pure rutile TiO2 film photoanode can be attributed to the Ti3+ doping in the bulk and high reactivity of the {111} crystal facets. Such a pure rutile TiO2 film with highly reactive (111) surfaces is a promising material for visible light photocatalysis and solar energy conversion.