Activating Carbon Nitride by BP@Ni for the Enhanced Photocatalytic Hydrogen Evolution and Selective Benzyl Alcohol Oxidation

Two-dimensional (2D) semiconductors are promising photocatalysts; in order to overcome the relatively low efficiency of single-component 2D photocatalysts, heterostructures are fabricated for effective charge separation. Herein, a 2D heterostructure is synthesized by anchoring nickel nanoparticle-decorated black phosphorus (BP) nanosheets to graphitic carbon nitride (CN) nanosheets (CN/BP@Ni). The CN/BP@Ni heterostructure exhibits an enhanced charge separation due to the tight interfacial interaction and the cascaded electron-transfer channel from CN to BP and then to Ni nanoparticles. Possessing abundant active sites of Ni and P-N coordinate bonds, CN/BP@Ni shows a high visible-light-driven H₂ evolution rate of 8.59 mmol·h^-1·g^-1 with the sacrificial agent EtOH, about 10-fold to that of CN/BP. When applying benzyl alcohol to consume photogenerated holes, CN/BP@Ni enables the selective production of benzaldehyde; therefore, two value-added products are obtained in a single closed redox cycle. This work provides new insights into the development of photocatalysts without non-noble metals.