Hybridization of brookite TiO2 with g-C3N4: a visible-light-driven photocatalyst for As3+ oxidation, MO degradation and water splitting for hydrogen evolution

This work gives a first report on the effective visible-light-driven photocatalyst of brookite TiO2 (br-TiO2) hybridized with g-C3N4. This hybrid was prepared via a facile calcination in air. When irradiated under visible light, all br-TiO2/g-C3N4 hybrids showed an activity superior to the component g-C3N4 or br-TiO2 in methyl orange (MO) degradation. The optimum photocatalytic activity of the hybrid br-TiO2/g-C3N4 is higher than those of other types of TiO2 (anatase and rutile) when hybridized with g-C3N4. Furthermore, the optimized hybrid, br-TiO2/g-C3N4 (35 wt%), was successfully applied to toxic As3+ oxidation and water splitting for hydrogen generation under visible light. All these results clearly demonstrate that the hybridization of br-TiO2 with g-C3N4 is highly promising for photocatalytic uses, which are barely accessible in previous literature. This abnormal observation is ascribed to the effective separation of the photo-generated carriers on the surfaces between the closely contacted br-TiO2 and g-C3N4.