Edge-effect enhanced catalytic CO oxidation by atomically dispersed Pt on nitride-graphene

Abstract

Single-atom catalysis has been of intense interest in recent years. Here, using first-principles simulations, we report a unique approach that obtains promising information about O₂ activation and CO oxidation on active Pt-single-atom catalysts (Pt-SACs) on N-doped graphene (NGr). It is found that the activity of Pt-SACs can be tuned by changing the Pt-loading sites on Gr/NGr, with Pt on the zigzag edge of NGr having optimal performance. Employing charge analysis of various anchoring sites, we reveal that the catalytic performance has a strong dependence on the polarization charge on the Pt atoms. The correlations of these charges with binding energies and reaction barriers exhibit volcano-like trends. The polarization charge thus provides a parameter that allows predicting the catalytic properties for different active sites, providing insights into the electronic structure modulation of SACs on graphene-like supports.