A Cu+1/Cu0 -TiO2 mesoporous nanocomposite exhibits improved H2 production from H2O under direct solar irradiation

A photostable sunlight-responsive mesoporous Cu+1/Cu-0-TiO2 (Cu-mpTiO(2)) photocatalyst has been fabricated for the H-2 production from water. Structural analysis revealed the anatase polymorph of TiO2 with mesoporous characteristics and an average particle size of similar to 32 nm. Mesoporous TiO2 was observed to possess high surface area (188 m(2) g(-1)) and pore size (0.32 nm). HRTEM studies suggested the deposition of Cu in Cu-0 and Cu+1 oxidation states with three distinct lattice fringes of 0.21, 0.25, and 0.35 nm for Cu, Cu2O, and TiO2 respectively. Cu-mpTiO(2) produced 1000 umol of H-2 (AQE = 11.39%) under sunlight irradiation, which is severalfold more than obtained with Cu impregnated on commercial Cu-TiO2 (P25). The photostability of the Cu-mpTiO(2) increased after recycling because the excess Cu+1 (binding energy = 533.5 eV) is reduced to Cu (533.3 eV) and the excess holes in the valance band of Cu2O oxidize Cu-0 to Cu+1. (C) 2016 Elsevier Inc. All rights reserved.