Au-Pt heterostructure cocatalysts on g-C3N4 for enhanced H2 evolution from photocatalytic glucose reforming

Abstract

Glucose from plants or food industry wastes is a cost-effective hole scavenger for photocatalytic water splitting, but the related H2 evolution rate is always restricted by the fast recombination of photo electron-hole pairs and the poor intrinsic activity of traditional Pt cocatalysts. Herein, we fabricated Au-Pt heterostructure cocatalyst that consist of one ∼3 nm Au core and several ∼1 nm Pt islands on ultrathin g-C3N4 through one-pot photo-deposition. The heterostructure exhibited superior H2 evolution activity to monometallic Au or Pt nanoparticles. Our experiments and theoretical calculations demonstrated that the enhanced activity was caused by the synergistic effect between Au and Pt, rather than the well-known plasmonic effect of Au. The heterostructure not only favored the trapping of photo electrons from g-C3N4, but also had suitable adsorption strength of H*, exhibiting high intrinsic activity towards H2 evolution. Our research provides a strategy to boost photocatalytic H2 evolution by regulating the synergy of bimetallic cocatalysts.