Carbon nitride based Schottky junction with a Ni–Mo synergistic interaction for highly efficient photocatalytic hydrogen production

Abstract

It remains a great challenge to develop low cost cocatalysts with comparable performance to noble metals for photocatalytic hydrogen evolution. Herein, in situ growth of nanosized bimetallic phosphides NiMoP₂ on graphite carbon nitride (CN) is realized. The synergistic interaction between Ni and Mo and the intimate CN/3NiMoP₂ Schottky junction greatly accelerates the separation of photogenerated charge carriers and the extraction from CN, as well as maintain the stability of H₂ production. The optimized CN/3NiMoP₂ achieves a more advantageous H₂ yield of 783 μmol g⁻¹ h⁻¹ and a corresponding apparent quantum efficiency of 3.9% at 420 nm, which are much better than that of CN and 3NiMoP₂ composite that is synthesized via non-in situ methods (CN–3NiMoP₂), indicating the importance of Schottky junction formation via the in situ preparation method. More importantly, CN/3NiMoP₂ demonstrates a comparable photocatalytic hydrogen production performance to CN/3 wt% Pt (770 μmol g⁻¹ h⁻¹) and satisfactory stability (21 h). This work provides a new route to synthesize low-cost cocatalysts that are expected to replace Pt in the field of photocatalytic hydrogen production.