Towards the prominent cocatalytic effect of ultra-small CoP particles anchored on g-C₃N₄ nanosheets for visible light driven photocatalytic H₂ production

In this work, we prepared a series of novel quasi 0D/2D nanohybrids of CoP/g-C₃N₄ derived from the composites of Co₃O₄ quantum dots with g-C₃N₄ nanosheets. Particularly, 0.45 wt% CoP modified g-C₃N₄ had the highest H₂ generation rate as 1.074 mmol·h⁻¹ g⁻¹ (AQY: 6.1% at 420 nm) under visible light irradiation, which was 283 and 5 times of that for pure g-C₃N₄ (0.0038 mmol·h⁻¹ g⁻¹) and 0.5 wt% Pt/g-C₃N₄ (0.216 mmol·h⁻¹ g⁻¹), respectively. The excellent performance was attributed to the formation of a new electron transfer route owing to the interaction of Co atoms with N atoms, the reaction sites of metal-like Co-P bonds due to the lower energy barrier than Pt toward H₂ evolution, and finally the well dispersed CoP nanoparticles offering much more reaction sites than bulk counterpart. Our work provides a new methodology to construct highly dispersed noble metal free cocatalyst in the matrix of host photocatalyst with excellent performance.