Efficient TiO2 photocatalysts from surface hybridization of TiO2 particles with graphite-like carbon

Surface hybridization of TiO2 with graphite-like carbon layers of a few molecular layers thickness yields efficient photocatalysts. Photoclectrochemical measurements confirm an electronic interaction between TiO2 and the graphite-like carbon. A TiO2 photocatalyst with a carbon shell of three molecular layers thickness (similar to 1 nm) shows the highest photocatalytic activity which is about two times higher than that of Degussa P25 TiO2 under UV light irradiation. The mechanism of the enhanced photocatalytic activity under UV irradiation is based on the high migration efficiency of photoinduced electrons at the graphite-like carbon/TiO2 interface, which is due to the electronic interaction between both materials. In addition, a high activity under visible light irradiation is observed after graphite-like carbon hybridization. TiO2's response is extended into the visible range of the solar spectrum due to the electronic coupling of pi states of the graphite-like carbon and conduction band states of TiO2.