In Situ Reinforced g-C3N4/CoO/CoP Ternary Composite for Enhanced Photocatalytic H2 Production

To meet the growing demand for renewable energy, developing efficient and cost-effective photocatalytic materials is crucial. Specifically, designing photocatalysts with high charge separation efficiency and abundant hydrogen production active sites remains a key challenge for practical applications. In this study, a carbon nitride (g-C3N4)-based ternary photocatalyst has been constructed for enhanced photocatalytic H2 production without the need for precious metal cocatalysts. CoO nanoparticles were loaded onto the surface of g-C3N4 via in situ thermal decomposition. Subsequently, a series of g-C3N4/CoO/CoP ternary composites were successfully prepared using a direct one-step phosphorization method. Under optimized conditions, the g-C3N4/CoO/CoP catalyst exhibits a hydrogen evolution activity of 1277.9 μmol·g−1·h−1, which is 4 times higher than that of g-C3N4/CoO (with g-C3N4 alone showing no hydrogen evolution activity). Its performance is comparable to that of the commonly used Pt cocatalyst. The performance improvement may be attributed to the tight bonding of N-P bonds, which effectively promotes the transport of photogenerated carriers, while the increased loading of CoP provides more active sites. The results offer a promising strategy for designing efficient and low-cost photocatalytic materials.