Core–shell amorphous cobalt phosphide/cadmium sulfide semiconductor nanorods for exceptional photocatalytic hydrogen production under visible light

Abstract

Efficient hydrogen (H₂) production is considered to be a key pathway for future clean energy supply. Herein we report that a photocatalyst made of core–shell amorphous cobalt phosphide (CoP_x) integrated with cadmium sulfide nanorods (CdS NRs) gives exceptional performance of photocatalytic H₂ production under visible light. Under optimal conditions, the CoP_x/CdS NRs photocatalyst allows an H₂ evolution rate of ∼500 μmol h⁻¹ mg⁻¹ based on the photocatalyst (λ > 420 nm) and the apparent quantum yield was ∼35% in aqueous solutions (λ = 450 nm). The turnover numbers (TONs) reached ∼630 000 per mole of cobalt in 70 hours with a TOF of ∼9000 h⁻¹. Such high performance of an artificial photosynthetic H₂ production system using a cobalt-based cocatalyst has, to the best of our knowledge, not been reported to date.