Bimetallic nitride NiMoN loaded on graphitic carbon nitride for plasmon-enhanced visible light-driven photocatalytic hydrogen evolution from water splitting

Abstract

Graphitic carbon nitride (g-C₃N₄) has attracted considerable interest due to its substantial role in photocatalytic hydrogen (H₂) production. Nevertheless, pristine g-C₃N₄ has several drawbacks, including poor optical absorption ability and rapid recombination of photogenerated charge carriers. In this study, bimetallic nitride NiMoN nanoparticle (NPs) loading onto g-C₃N₄ termed as CN-NiMoN plasmonic heterojunctions were prepared to enhance the photocatalytic H₂ evolution from water splitting under visible light irradiation (λ ≥ 420 nm). The obtained CN-xNiMoN (x represents the weight content of NiMoN) plasmonic photocatalysts exhibited efficient H₂ generation under visible light illumination. The optimal CN-1NiMoN photocatalyst achieved a maximum H₂ evolution of 75.26 μmol h⁻¹ under visible light irradiation, which is 5.4 times higher than that of g-C₃N₄. Moreover, the optimal CN-1NiMoN sample exhibited an apparent quantum yield (AQY) of 6.24% at a wavelength of 420 nm. This enhanced activity is attributed to the efficient separation and transfer of photoexcited charge carriers and the surface plasmon resonance (SPR) effect of bimetallic nitride NiMoN NPs. This work paves a new path to develop plasmonic nanomaterial-modified semiconductor-based photocatalysts for practical applications in solar-to-hydrogen energy conversion.