Ti3+-TiO2/g-C3N4 mesostructured nanosheets heterojunctions as efficient visible-light-driven photocatalysts

Ti 3+ self-doped TiO 2 /g-C 3 N 4 mesostructured nanosheets heterojunctions (Ti 3+ -TiO 2 /Meso-g-C 3 N 4 ) have been prepared via calcination-sonication assisted method using amino cyanamide as precursors, combined with a solid-state chemical reduction method. The Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions with narrow band gap of ∼2.21 eV possess relative high surface area of ∼73.8 m 2  g −1 , and large pore size of ∼10 nm. Remarkably, the Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions exhibit excellent visible-light-driven photocatalytic activity for degradating phenol in wastewaters. The photocatalytic hydrogen production rate of Ti 3+ -TiO 2 /Meso-g-C 3 N 4 heterojunctions rise to ∼290.2 μmol h −1  g −1 , which is about 4 and 14 times higher than that of the bare Meso-g-C 3 N 4 and TiO 2 , respectively. The enhanced photocatalytic activity may be ascribed to the synergetic effect of the mesoporous structure providing sufficient surface active sites, and Ti 3+ self-doping and the formed heterojunctions promoting the spatial separation of photogenerated electron-hole pairs.