The Synergistic Effect in CdS/g-C(3)N(4) Nanoheterojunctions Improves Visible Light Photocatalytic Performance for Hydrogen Evolution Reactions

This study focuses on the development of heterojunction photocatalysts for the efficient utilization of solar energy to address the energy crisis and reduce environmental pollution. Cadmium sulfide (CdS)/graphite-type carbon nitride (g-C(3)N(4)) nanocomposites were synthesized using a hydrothermal method, and their photoelectrochemical properties and photocatalytic performance for hydrogen evolution reaction (HER) were characterized. Scanning electron microscope images showed the intimate interface and caviar-like nanoheterojunction of the CdS nanoparticles on g-C(3)N(4) nanospheres, suggesting their potential involvement in the photocatalytic process. Electrochemical and spectroscopic analyses were conducted to confirm the roles of CdS in the nanoheterojunction. The results showed that 10 wt% CdS/g-C(3)N(4) nanospheres exhibited higher photocatalytic activity than pure g-C(3)N(4) under visible light irradiation. A HER rate of 655.5 μmol/g/h was achieved after three photocatalytic cycles, signifying good photocatalytic stability. The synergistic effect of the Z-scheme heterojunction formed by g-C(3)N(4) and CdS was identified as the main factor responsible for the enhanced photocatalytic performance and stability. The interface engineering effect of CdS/g-C(3)N(4) facilitated the separation of photogenerated electrons and holes. This study provides insights into the design and fabrication of efficient HER photocatalysts.