Efficient hydrogen production from renewable energy sources is the most important requirement to produce clean fuels. Developing materials systems with high activity and good stability for solar energy conversion has become one of the most prominent and challenging research fields in the interdisciplinary scientific community. The narrowing of the gap is caused by band-like states appearing below the conduction band, which are mainly contributed by carbon atoms surrounding the defect. It is further observed that the Fermi energy has been shifted to the bottom of the conduction band, indicating n type behavior. The impurity induced states are not localized on H atoms. In contrary to the common electronic structure produced by the defects, this case is different. Examples of defect localized states include N and Cu doping in oxides.10,11 Impurity localized states may act as recombination center; however, in this case, the photo-excited electrons are not localized and are easy to separate.