Ab initio study of surface stress response to charging

TL;DR

This study presents a computational method to evaluate how surface stress in metals responds to charging, using density functional theory to analyze different gold surfaces and explaining experimental volume changes in charged nanoporous materials.

Contribution

It introduces an efficient numerical approach to assess surface stress response to charging based on work function strain dependence, applied to gold surfaces with results aligning with experiments.

Findings

Surface stress response parameter sign correlates with surface dipole and Fermi energy dependence on strain.

Numerical response values match experimental ranges.

Magnitude of response explains volume changes in nanoporous materials upon charging.

Abstract

We explore an efficient way to numerically evaluate the response of the surface stress of a metal to changes in its superficial charge density by analysis of the strain-dependence of the work function of the uncharged surface. As an application we consider Au(111), (110) and (100) surfaces, employing density functional calculations. The sign of the calculated response parameter can be rationalized with the dependence of the surface dipole and the Fermi energy on strain. The numerical value falls within the range indicated by experiment. The magnitude can explain the experimentally observed volume changes of nanoporous materials upon charging.