Multi-Lattice Kinetic Monte Carlo Simulations from First-Principles: Reduction of the Pd(100) Surface Oxide by CO

TL;DR

This paper introduces a multi-lattice kinetic Monte Carlo method based on first-principles calculations to simulate the reduction of PdO surfaces by CO, accurately capturing experimental temperature-dependent reduction rates.

Contribution

It develops a novel multi-lattice kMC approach from first-principles data to model surface oxide reduction processes with high accuracy.

Findings

Simulates oxide reduction rate matching experimental data

Highlights importance of boundary-specific elementary processes

Provides detailed atomistic pathway for PdO reduction

Abstract

We present a multi-lattice kinetic Monte Carlo (kMC) approach that efficiently describes the atomistic dynamics of morphological transitions between commensurate structures at crystal surfaces. As an example we study the reduction of a $(\sqrt{5}\times \sqrt{5})R27^{\circ}$ PdO(101) overlayer on Pd(100) in a CO atmosphere. Extensive density-functional theory calculations are used to establish an atomistic pathway for the oxide reduction process. First-principles multi-lattice kMC simulations on the basis of this pathway fully reproduce the experimental temperature dependence of the reduction rate [Fernandes et al., Surf. Sci. 2014, 621, 31-39] and highlight the crucial role of elementary processes special to the boundary between oxide and metal domains.