Design of a CO Oxidation Catalyst Based on Two-Dimensional MnO2

Abstract

Two-dimensional (2D) MnO2 monolayer can be prepared by delamination of a layered manganese oxide. Herein, for the first time, we design a 2D MnO2-based catalyst for CO oxidation reaction through density functional theory calculations. We found that pristine MnO2 sheet does not exhibit high catalytic activity for CO oxidation, while active sites can be created by doping MnO2 with transition metal elements. We examined the effects of substitutional doping of MnO2 with Ru, Rh, Pd, Pt, and Au. The calculated energetic profiles of CO oxidation suggest that the reaction proceed very facile with a Mars–van Krevelen mechanism on Ru-doped MnO2 monolayer, while it is less likely to occur for other doped systems including Rh, Pd, Pt, and Au as well as the pristine MnO2. The discrepancy of catalytic activities is rationalized by electronic structure calculations. We expect this study can shed light on the development of low-temperature CO oxidation catalysts.