Synchronous construction of Ni2P/Cu3P in-situ loading and P doping for g-C3N4: Enhanced photocatalytic H2 evolution activity and mechanism

Abstract

Research on the subject of photolysis focuses on the creation of effective non-precious metal co-catalysts. Graphitic carbon nitride (g-C3N4) is a promising candidate for photocatalytic hydrogen generation from water. But its photocatalytic activity is limited by the slow redox reaction, high carrier recombination rate, and inadequate optical absorption. Incorporating in situ loading Ni2P/Cu3P and phosphorus doping on g-C3N4 is effective in overcoming the drawbacks. Phosphorus doping reduces the band gap of g-C3N4 for increased light absorption and improves the separation of photogenerated charge. Additionally, Ni2P/Cu3P heterojunctions anchored on P-doped g-C3N4 (P-C3N4) as non-noble co-catalysts boost light adsorption, enabling charge transfer and speeding the hydrogen evolution process. The resultant Ni2P/Cu3P@P-C3N4 composite photocatalyst achieves an effective photocatalytic hydrogen evolution rate of 201 times greater than that of g-C3N4 (12.9 μmol·h−1·g−1). This work is instructive to develop efficient g-C3N4-based photocatalysts for photocatalytic water splitting without the need for noble metals.