Surface stress of clean and adsorbate-covered solids

Abstract

Starting with a simple introduction into the phenomenon of surface stress from a thermodynamic as well as from an atomistic viewpoint, the currently available literature on surface stress of clean and adsorbate-covered surfaces is reviewed. The equations which are used to calculate the adsorbate-induced changes of the surface stress tensor from cantilever bending experiments are derived and their limitations are discussed. It is shown for several examples that charge transfer effects have a pronounced influence on the adsorbate-induced surface stress. The linear relation between surface stress and surface charge which has been observed experimentally at the metal-electrolyte interface is rationalized in the framework of thermodynamics. The role of surface stress as a driving force for surface reconstruction and for the structural organization of surfaces on a mesoscopic scale are discussed for a few selected examples. Novel applications of surface stress effects for sensor and actuator applications are described.

Adsorption-induced deformation of nanoporous materials—A review

“…The appearance of more precise measurements from Haines and McIntosh 9 showed that the strain isotherms for microporous materials have a small region where the samples contract, which could not be explained by Bangham's equation (3). The contraction in the beginning of the strain isotherm was further confirmed in several other experimental works 10,77,78 and the following explanation was given by Lakhanpal and Flood.…”

“…There has been a vast literature on stresses at the plain surfaces induced by gas or electrolyte adsorption, many of which are summarized in a seminal review by Haiss. 3 …”

“…An instructive review on the surface stress in nonporous materials and effects of adsorption on it has been given by Haiss. 3 The surface stress has been studied theoretically for a number of systems in which the guest atoms are chemisorbed on the surface. [146][147][148][149] When adsorbed atoms are chemically bound to the solid surface, the change in surface free energy is dominated by the enthalpy, and the surface stresses can therefore be readily calculated from the electronic structure density functional theory (eDFT) on the static atomic configurations.…”

Nanoparticle Structure by Coherent X-ray Diffraction

“…Surface stresses, measured by a variety of methods, for metals are usually tensile and relatively large, in the range of 2 N/m. 3,4) These are of course strongly influenced by the details of any surface reconstruction and the adsorption of foreign species, hence whether or not the surface is cleaned to the high standards of ultrahigh vacuum (UHV) conditions. If such a stress is present on the surface of a spherical particle of radius R, the surface stress S will give rise to a pressure difference ÁP between the inside and outside, according to the classical Gibbs-Thomson equation, otherwise known as the Young-Laplace equation, used to explain the stability of soap bubbles among many other applications:…”

Charge redistribution in electrochemically actuated mechanical sensors

“…An investigation of the double-layer region [10][11][12][13] (i.e., when no electrochemical reaction occurred) as well as 3 adsorption reactions [14][15][16][17] and electrodeposition [18] have been carried out using the standard optical lever technique [1].…”