Superiority and mechanism of Pt oriented-deposition in improving the photocatalytic activity of TiO2 sphere with exposed {0 0 1} facet

• TiO2 spheres with wholly exposed {001} facets are prepared;
• Pt oriented-deposition on the TiO2 surface is obtained;
• Pt oriented-deposition is superior to Pt random-deposition for photocatalysis;
• {001} facet is served for photo-oxidation;
• The edge between {001} and {101} facets is served for photo-reduction.

Transfer and aggregation of photogenerated electrons and holes on anatase TiO2 sphere with wholly exposed {0 0 1} facets are investigated by Pt oriented-deposition. Results indicate the Pt particles are all deposited on the edge, which is served for photo-reduction, between the {0 0 1} and {1 0 1} facets. The {0 0 1} facets will serve for photo-oxidation. This structure is superior to that of Pt random-deposition, resulting in higher efficiency in separating photogenerated electrons and holes. Proper amount of deposited Pt is also an important factor in affecting the photocatalytic activity of TiO2. Photocatalytic degradation of RhB and phenol suggest the as-prepared photocatalysts can be efficient candidates for decomposing organic pollutants.