Modulating the Electronic Properties and Hydrogen Evolution Reaction Performance of Precious-Metal on 2D-SiC via Surface Defect

Abstract

2D-SiC exhibits considerable potential for optoelectronic applications. However, its intrinsic electronic structure limit broader applicability, particularly in electrocatalytic hydrogen evolution reaction (HER) research, which remains underexplored. In this paper, we employed firstprinciples calculations to systematically investigate the binding strength, electronic properties, magnetic characteristics, and HER performance of precious-metal (PM=Ru, Rh, Pd, Ag, Os, Ir, Pt, Au) single-atom catalysts (SACs) supported on vacancy-defective 2D-SiC. Our findings reveal that the binding strength and HER performance of PM-supported at Si-vacancy are markedly superior to those supported at C-vacancy. Within Si-vacancy-supported PM systems, the binding strength of PM on 2D-SiC increases with higher doping concentrations. Analysis of the HER activity for Pd and Pt-SACs at Si-vacancy indicates that, within the same PM-supported system, a greater distance between the d-band-center and the Fermi level correlates with enhanced HER activity. Notably, the Pt-SACs supported at Si-vacancy in a 3×3×1 2D-SiC supercell exhibits excellent thermal stability and outstanding HER performance. In addition, PM-SACs-supported on vacancy-defective 2D-SiC display rich electronic and magnetic properties, and magnetic contribution analysis demonstrates that Si atoms do not contribute to the magnetism of the supported systems. These findings provide theoretical insights for the future application of 2D-SiC in electronic devices and electrocatalytic materials.