Constructing Dual Cocatalysts of Ni 2 P-NiS-Decorated TiO 2 for Boosting Photocatalytic H 2 Evolution

The loading of cocatalysts is an effective approach to optimize the separation of carriers during photocatalytic processes. Among them, cocatalysts often work independently during the photocatalytic production of H . However, an investigation of the synergistic effect of dual cocatalysts is beneficial for further promoting photocatalytic H production activity. In this work, dual cocatalyst Ni P-NiS-modified TiO nanosheets were fabricated through a solvent evaporation method. The investigation indicates that Ni P-NiS can widen the light absorption range and reduce the contact angle between TiO and water from 26.71 to 8.27°, which facilitates the adsorption of water molecules. Besides, the introduction of Ni P-NiS can decrease the overpotential of H evolution and induce more electrochemically active surface area. The photocatalytic tests show that the H production rate of 15% Ni P-NiS/TiO can reach up to 4891.6 μmol·g ·h , which is 30.2, 4.4, and 1.3 times than pure TiO (161.8 μmol·g ·h ), 15% Ni P/TiO (1112.1 μmol·g ·h ), and 15% NiS/TiO (3678.1 μmol·g ·h ), respectively. The enhancement mechanism of photocatalytic H production is attributed to the Schottky barrier effect between Ni P-NiS nanoparticles and TiO nanosheets, which can enormously promote the interface charge separation and transfer, and enhance the kinetics of H production. This work provides a potential strategy for enhancement H production using appropriate dual cocatalyst-decorated semiconductor materials.