Ni-anchored g-C3N4 for improved hydrogen evolution in photocatalysis.

In this study, we present a facile wet chemical method for synthesizing Ni-modified polymeric carbon nitride (g-C3N4) nanosheets. X-ray absorption fine structure spectroscopy (XAFS) reveals the formation of a unique Ni-N structure, resulting from Ni atoms anchoring in cavities of g-C3N4. The Ni anchoring on the surface N sites modifies the electronic structure of g-C3N4, demonstrating remarkable effectiveness even at low anchoring amounts. The as-prepared Ni/g-C3N4 catalysts show robust performance for photocatalytic hydrogen evolution under visible light irradiation, attributed to the unique Ni-N interactions. Specifically, the photocatalytic H2 production rate of the Ni/CN-45 catalyst reached 8482.14 μmol·g-1·h-1 with an apparent quantum efficiency (AQE) of 0.75% under light irradiation at 427 nm. This rate surpasses most of the previously reported g-C3N4 based photocatalysts and is nearly 8 times higher than that of the pure g-C3N4 catalyst (1116.07 μmol·g-1·h-1). .