A theoretical study of single-atom catalysis of CO oxidation using Au embedded 2D h-BN monolayer: a CO-promoted O? activation.

ABSTRACT: The CO oxidation behaviors on single Au atom embedded in two-dimensional h-BN monolayer are investigated on the basis of first-principles calculations, quantum Born-Oppenheim molecular dynamic simulations (BOMD) and micro-kinetic analysis. We show that CO oxidation on h-BN monolayer support single gold atom prefers an unreported tri-molecular Eley-Rideal (E-R) reaction, where O2 molecule is activated by two pre-adsorbed CO molecules. The formed OCOAuOCO intermediate dissociates into two CO2 molecules synchronously, which is the rate-limiting step with an energy barrier of 0.47?eV. By using the micro-kinetic analysis, the CO oxidation following the tri-molecular E-R reaction pathway entails much higher reaction rate (1.43 × 10(5)?s(-1)) than that of bimolecular Langmuir-Hinshelwood (L-H) pathway (4.29?s(-1)). Further, the quantum BOMD simulation at the temperature of 300?K demonstrates the complete reaction process in real time.

SUBMITTER: Mao K 

PROVIDER: S-EPMC4069717 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature