A silver on 2D white-C3N4 support photocatalyst for mechanistic insights: synergetic utilization of plasmonic effect for solar hydrogen evolution

Abstract

A photocatalyst integrating silver surface plasmon effect into two-dimensional g-C₃N₄ nanosheets (2D white-C₃N₄) was prepared successfully. The crystal structure, chemical states, morphology and photocatalytic performance of the prepared samples were researched by the comprehensive characterization methods. The photocatalytic activities of Ag/2D white g-C₃N₄ composites were dramatically enhanced under visible light irradiation. When Ag content was optimized, 2% Ag/white g-C₃N₄ exhibited the best photocatalytic activity. The electrochemical investigation verified the role of the hot electrons from the plasmonic Ag in the photocatalytic reaction. The plasmonic hot electron injection and advantages of 2D ultrathin structure improved the density of the electrons with reducibility and led to more efficient separation of photogenerated electron and hole pairs. The photocatalytic mechanism was also researched in detail via ESR analysis.