Dual-phase metal nitrides as highly efficient co-catalysts for photocatalytic hydrogen evolution

Low solar-to-fuel conversion in conventional semiconductor-based photocatalysts limits their commercial applications. Searching for highly efficient cost-effective co-catalysts is desirable for the development of artificial photosynthesis systems. In this work, we report a simple yet efficient electrostatic self-assembly process to synthesize one-dimensional Co 4 N-WN x -CdS composites for visible light-driven hydrogen evolution in pure water. Biphasic transition metal nitrides Co 4 N-WN x with high conductivity and enriched active sites leads to multi-level electrons transfer and lower over-potential for hydrogen production. Co 4 N-WN x -CdS composite, with optimized wt%, exhibits the highest rate of photocatalytic hydrogen evolution (14.42 mmol g −1 h −1 ) under vacuum condition. This rate is ~ 8 times higher than that of the Pt-CdS composite (1.78 mmol g −1 h −1 ).