Amorphization-induced reverse electron transfer in NiB cocatalyst for boosting photocatalytic H2 production

Regulating the electron density distribution of active sites to accelerate catalytic process is of great significance to explore high-efficiency cocatalysts for photocatalytic hydrogen production. In this work, a novel strategy of amorphization-induced reverse electron transfer is proposed to optimize the electronic structure of Ni active site in nickel boride (NiB) cocatalyst to promote the photocatalytic hydrogen-production activity of TiO2. Herein, the NiB nanodots (0.5–1 nm) with an amorphous structure can perfectly be anchored onto TiO2 surface via a novel-designed light-induced route. The resulting amorphous-NiB/TiO2 sample achieves the photocatalytic H2-production rate of 2334.0 μmol h−1 g−1, which is 1.8 times higher than that of the traditional crystalline-NiB/TiO2 photocatalyst. The experimental and theoretical investigations confirm that the amorphization of NiB can induce the reverse electron transfer from B to Ni, which can promote the hydrogen desorption process of the Ni active site to boost the H2-production efficiency. This work paves a new way for active site optimization and delivers in-depth insights for the exploration of high-efficient hydrogen-production cocatalysts. [Display omitted] •An amorphization-induce reverse electron transfer idea was proposed to optimize NiB.•A photodeposition route was designed to obtain the amorphous NiB cocatalyst.•The amorphous NiB cocatalyst can markedly boost the H2-evolution activity of TiO2.•The a-NiB/TiO2 showed an enhanced H2-evolution activity than the c-NiB/TiO2.