Identification of the Charge Transfer Channel in Cobalt Encapsulated Hollow Nitrogen-Doped Carbon Matrix@CdS Heterostructure for Photocatalytic Hydrogen Evolution

Water splitting to H-2 by photocatalysis remains an effective strategy to alleviate the energy crisis. Unfortunately, single-component photocatalyst still suffers from sluggish reaction kinetics. In this work, a noble-metal free photocatalytic system of nitrogen-doped carbon@Co embedded in carbon nanotubes (NC@Co-NCT)/cadmium sulfide (CdS) is fabricated by coupling CdS nanorods with the metal-organic framework-derived Co encapsulated nitrogen-doped carbon (NC) material. The optimal photocatalytic activity of NC@Co-NCT/CdS is determined to be 3.8 mmol h(-1) g(-1), which is approximate to 5.8 times of CdS. By combining the experimental evidences and density functional theory calculations, a novel photoelectron transfer channel in the heterojunction interfaces is revealed, expediting the migration and separation of photo-induced charge carriers of CdS. Moreover, the presence of Co nanoclusters can act as the active sites, boosting the H-2 evolution reaction. This study can present a new avenue to design advanced photocatalysts with high-efficiency electrons and holes separation.

Automated summary

A noble-metal free photocatalytic system of NC@Co-NCT/CdS was fabricated to enhance water splitting for H-2 production. The optimal photocatalytic activity of NC@Co-NCT/CdS was found to be 3.8 mmol h(-1) g(-1), approximately 5.8 times that of CdS. This study reveals a novel photoelectron transfer channel in the heterojunction interfaces, facilitating the migration and separation of photo-induced charge carriers of CdS, and suggests that Co nanoclusters can act as active sites to boost the H-2 evolution reaction.