Control of Spatially Homogeneous Distribution of Heteroatoms to Produce Red TiO Photocatalyst for Visible-Light Photocatalytic Water Splitting.

The strong band-to-band absorption of photocatalysts spanning the whole visible-light region (400-700 nm) is critically important for solar-driven photocatalysis. Although it has been actively and widely used as a photocatalyst for various reactions in the past four decades, TiO has a very poor ability to capture the whole spectrum of visible light. In this work, by controlling the spatially homogeneous distribution of boron and nitrogen heteroatoms in anatase TiO microspheres with a predominance of high-energy {001} facets, a strong visible-light absorption spectrum with a sharp edge beyond 680 nm has been achieved. The red TiO obtained with homogeneous doping of boron and nitrogen shows no increase in defects like Ti that are commonly observed in doped TiO . More importantly, it has the ability to induce photocatalytic water oxidation to produce oxygen under the irradiation of visible light beyond 550 nm and also the photocatalytic reduction of water to produce hydrogen under visible light. These results demonstrate the great promise of using red TiO for visible-light photocatalytic water splitting and also reveal an attractive strategy for realizing the wide-spectrum visible-light absorption of wide-band-gap oxide photocatalysts.