Atomically Precise Metal Nanocluster-Mediated Photocatalysis

Atomically precise thiolate-capped metal nano-clusters (NCs), as a recently developed category of metalnanomaterials, show emerging potential in solar energy harvestingand conversion owing to the peculiar atom-stacking mode,quantum confinement effect, and discrete energy band structure.However, the super-short photoexcited charge carrier life span andbarren active sites of metal NCs as well as instability retard thephotosensitization efficiency in photoredox catalysis. Herein, weconceptually demonstrate thegeneral design of glutathione(GSH)-capped metal NCs/transition metal chalcogenides(TMCs), that is, metal NCs [Agx,Ag31(GSH)19,Ag16(GSH)9,Ag9(GSH)6]/TMC (CdS, Zn0.5Cd0.5S) heterostructures by aligand-initiated self-assembly route, based on which atomically precise metal NCs are accurately anchored on the TMC substratesunder substantial electrostatic interaction. It was unveiled that photoinduced electrons from metal NCs canflow to the TMCsubstrates and holes migrate in an opposite direction, featuring the quintessential type II charge transport pathway because of thesuitable energy level alignment, intimate interfacial integration mode, and boosted charge separation. Given the efficacious interfacialcharge migration/separation, metal NCs/TMC heterostructures exhibit significantly boosted photoactivities toward selective organictransformation and solar-to-hydrogen conversion under visible light irradiation. Our work would provide new insights into rationallycrafting metal NC-based photosystems and open a promising vista for modulating vectorial charge transfer over metal NCs towardsubstantial solar-to-chemical energy conversion.

Automated summary

Researchers have successfully designed a glutathione-capped metal nano-cluster/transition metal chalcogenides (TMCs) heterostructure through a ligand-initiated self-assembly route, and found that this structure can significantly enhance photocatalytic activity and solar energy conversion efficiency.