Carbonaceous-TiO2 nanomaterials for photocatalytic degradation of pollutants: A review

Semiconductor photocatalysis is one of most appealing and attractive technologies, which has been directly utilized to harvest solar energy for energy and environmental applications. Titanium dioxide (TiO2) has been proved to be leading semiconductor photocatalyst for the degradation of pollutants. However, it suffers from low photocatalytic activity under visible light activation because of its intrinsic wide band gap. Various strategies have been developed to enhance TiO2 efficiency in the visible light region. Among them TiO2 modification with carbonaceous nanomaterials is very effective route for excellent photocatalytic activity. This critical review aims to present recent progress in the design and synthesis of carbonaceous-TiO2 photocatalysts, covering carbon doping, activated carbon, fullerenes, carbon nanotubes and graphene. Moreover, proposed mechanisms of enhancement, effect of synthesis routes, demonstrations of performance and applications reported in literature are reviewed. Ongoing challenges and possible new directions are outlined.