Self-assembly induction of reduced graphene oxide decorated CdS nanoboxes for photocatalytic hydrogen evolution

Abstract

Solar-driven photocatalytic hydrogen evolution promises a bright future in responding to energy issues and environmental emergencies. Herein, we report a reduced graphene oxide decorated CdS (rGO-CdS) photocatalyst with a hollow nanobox morphology and an electronic structure via a facile and effective electrostatic self-assembly strategy for photocatalytic hydrogen evolution. Accordingly, with optimal rGO loading, the rGO-CdS-3 photocatalyst, benefiting from good visible-light harvesting ability, short carrier transport distance, and rich surface reactive sites, delivers a high photocatalytic hydrogen rate of 75.1 μmol h⁻¹ with strong redox capability and favorable photostability. Meanwhile, the establishment of the built-in interface electric field and Coulomb interaction in the rGO-CdS-3 photocatalyst significantly facilitate the space charge separation and accelerate the interfacial charge migration and transfer, which is beneficial to the overall photocatalytic hydrogen evolution. Experimental results coupled with DFT calculations further confirm the interfacial charge migration route from CdS to rGO. This work opens valuable avenues for fabricating CdS-based nanocomposites for solar-to-chemical energy conversion.