Dual interfacing with metallic cobalt boosts the electron shuttle of CdS-carbide nanoassemblies

Harnessing accelerated interfacial redox, thus boosting charge separation, is of great importance in photocatalytic solar hydrogen generation. In effect, nanoassembling non-noble metallic phases in CdS-based systems and elucidating their role in photocatalysis hold the key to eventually boosting electron shuttle in the field. Here we combine an efficient in-situ exsoluted metallic Co⁰ nanoparticles on a carbides matrix (CMG) with CdS (CdS@CoCMG) for photogeneration of hydrogen. The metallic cobalt phase exhibits strong binding at the CdS-carbide dual interfaces, forming the accelerated "electron converter" mechanism validated by charge transfer kinetics and achieving two orders of magnitude faster hydrogen production (44.42 mmol g^-1 h^-1) relative to CdS (0.43 mmol g^-1 h^-1). We propose that the unique catalyst configuration enable the directional electron-relay photocatalysis via harnessing interfaces between Co⁰ phase, carbides, and CdS clusters, which eventually boosts the redox process and charge separation of the integrated system, leading to high H₂ production rates in the suspension.