Crystal facet engineering of hollow cadmium sulfide for efficient photocatalytic hydrogen evolution

Metal sulfides have been considered as potential candidates for photocatalytic hydrogen production, but their practical applications are still limited by incident light utilization and charge separation despite the impressive advances in recent decades. To address these challenges, the construction of hollow nanostructure with exposing high active facets offers a desirable pathway for developing novel and high-efficiency photocatalysts. Here, by taking wurtzite CdS as an example, we first develop a general template-assisted cation exchange route for the preparation of hollow CdS nanostructures with diverse exposed facets. The obtained hollow CdS octahedrons with dominant {101} facets exhibit superior photocatalytic H2 evolution rate under visible-light irradiation compared with common CdS nanorods. According to the characterization results and density functional theory calculations, the excellent photocatalytic performance is attributed to the construction of hollow nano-octahedrons with exposed {101} active facets, which facilitates efficient light harvesting and photoinduced charge separation of CdS photocatalyst. The present approach gives a reference to design advanced semiconductors with remarkable photocatalytic activity for realizing efficient solar-to-chemical conversion.