The effects of Ni-loading on TiO2 nanoparticles can pronouncedly reduce the barriers for dissociation of H-2 from 48 kcal/mol on the pure TiO2 to as low as 1-3 kcal/mol on the loaded samples facilitating the hydrogenation of NPs. Preliminary data of our test indicate that the hydrogenation of Ni-loaded TiO2 NPs results in a significant UV-visible absorption extending well beyond 750 nm with an increase in water splitting efficiency by as much as 67 times over those of pure and hydrogenated TiO2 NPs without Ni-loading under our mild hydrogenation condition using 800 Torr of H-2 at 300 degrees C for 3 h. (C) 2016 Elsevier B.V. All rights reserved.