Black phosphorus-TiF3 photocatalyst for hydrogen production with an excellent capacity

Abstract Black phosphorus (BP) is a promising two-dimensional material with excellent carrier mobility and high co-catalytic activity for hydrogen generation. Herein, we use polycrystalline BP nanosheets as a photocatalyst and a structure of TiF3 as a cocatalyst to produce hydrogen under ultraviolet-visible (UV–vis) light irradiation. The TiF3-BP composite demonstrates a hydrogen evolution rate of 612 μmolh−1 g−1 and nearly perfect cyclic stability during 4 h irradiation. The evolution rate is about 1.7 times higher than those of pure BP and TiO2 and 1.5 times than that of commercial P25-BP mixture. In comparison with pure BP nanosheets, the addition of TiF3 can effectively tailor the energy levels of BP nanosheets, decrease the recombination of photogenerated electron-hole pairs, facilitate carrier transports, and improve the stability of BP exposed to water and air. Therefore, the above findings provide a new approach for designing stable and high efficiency BP composite photocatalysts for hydrogen production.