Dissociation of O2 molecules on strained Pb(111) surfaces

TL;DR

This study uses first-principles molecular dynamics to explore how oxygen molecules interact with strained Pb(111) surfaces, revealing strain-dependent dissociation behaviors and aligning with previous experimental findings.

Contribution

It provides new insights into how surface strain influences oxygen dissociation on Pb(111), combining dynamic simulations with prior static calculations.

Findings

O2 molecules do not dissociate on compressed Pb(111) with strain > 0.02

Surface stretching facilitates O2 approach and increases adsorption energy

Simulation results agree with previous static calculations and experimental data

Abstract

By performing first-principles molecular dynamics calculations, we systematically simulate the adsorption behavior of oxygen molecules on the clean and strained Pb(111) surfaces. The obtained molecular adsorption precursor state, and the activated dissociation process for oxygen molecules on the clean Pb surface are in good agreements with our previous static calculations, and perfectly explains previous experimental observations [Proc. Natl. Acad. Sci. U.S.A. 104, 9204 (2007)]. In addition, we also study the influences of surface strain on the dissociation behaviors of O2 molecules. It is found that on the compressed Pb(111) surfaces with a strain value of larger than 0.02, O2 molecules will not dissociate at all. And on the stretched Pb(111) surfaces, O2 molecules become easier to approach, and the adsorption energy of the dissociated oxygen atoms is larger than that on the clean Pb surface.