Examination of the key issues in microkinetics: CO oxidation on Rh(111)

Microkinetic modelling plays the key role to bridge first principles calculations at the atomic level to experimental data at macroscopic scales. Currently, some significant differences between the microkinetic modelling results and experimental ones still exist. In this work, CO oxidation on Rh(111) is selected as a model system for its simplicity as well as its importance, and an in-depth study of microkinetic modelling on the reaction is performed. A self-consistent microkinetic modelling iterating with respect to coverages is developed. It is found that a good accuracy of the microkinetic modelling using density functional theory energies can be obtained if adsorbate-adsorbate interactions including the coverage effect on the transition states are rigorously calculated. The calculated kinetic results including the turnover frequency (TOF), which are very close to experimental ones, can be achieved if corrections of the over-estimation of chemisorption energies of density functional theory and van der Waals forces are also included. (C) 2019 Elsevier Inc. All rights reserved.