Chapter 3
Potential- or Adsorbate-Induced
Changes in Surface Stress of Solid Metal
Electrode, and Surface Stress
versus Surface Charge Density
or Potential versus Surface Elastic Strain
Abstract Potential- or adsorbate-induced changes in surface stress associated with
surface reconstruction or adsorption of electrolyte anions on single-crystal Au
electrodes are explained and discussed as typical examples of the electro-chemomechanical properties. The surface stress versus potential curves measured for singlecrystal Au electrodes subjected to surface reconstruction or adsorption of electrolyte
anions are compared with the corresponding electrocapillary (surface tension vs.
potential) curves, and it is experimentally confirmed that surface stress differs from
surface tension for a solid electrode. Two important parameters for characterizing
solid electrode surfaces are surface stress–surface charge coefficient and potential–
surface elastic strain coefficient which are theoretically equivalent to each other. The
above two coefficients measured separately by several methods for a (111)-textured
Au (111) thin-film electrode in perchloric acid solution are compared, and the equality
of both coefficients is confirmed experimentally. Furthermore, the sign-reversals of
the above coefficients observed for nano-porous or (111)-textured Pt electrodes in
acid solutions are explained and the causes of the sign-reversal are discussed on the
basis of the changes in electronic structure of the electrode surfaces.
Keywords Surface stress · Surface reconstruction · Adsorption · Surface
stress–surface charge density coefficient · Potential–surface elastic strain
coefficient
3.1 Introduction
Potential- or adsorbate-induced changes in surface stress associated with surface
reconstruction or adsorption of electrolyte species on a solid electrode are typical
examples of the electro-chemo-mechanical properties. The changes in surface stress
of single-crystal Au electrodes for surface reconstruction or adsorption of electrolyte
anions have been measured as function of applied potential or surface charge density
by a cantilever bending method. On the other hand, the concomitant changes in
surface tension of single-crystal Au electrodes can be estimated by using the Lippmann equation from the measurement of differential capacity or surface charge
density. In the present chapter, we compare the surface stress versus potential curves
© Springer Nature Singapore Pte Ltd. 2020
M. Seo, Electro-Chemo-Mechanical Properties of Solid Electrode Surfaces,
https://doi.org/10.1007/978-981-15-7277-7_3
67
Potential- or Adsorbate-Induced
Changes in Surface Stress of Solid Metal
Electrode, and Surface Stress
versus Surface Charge Density
or Potential versus Surface Elastic Strain
Abstract Potential- or adsorbate-induced changes in surface stress associated with
surface reconstruction or adsorption of electrolyte anions on single-crystal Au
electrodes are explained and discussed as typical examples of the electro-chemomechanical properties. The surface stress versus potential curves measured for singlecrystal Au electrodes subjected to surface reconstruction or adsorption of electrolyte
anions are compared with the corresponding electrocapillary (surface tension vs.
potential) curves, and it is experimentally confirmed that surface stress differs from
surface tension for a solid electrode. Two important parameters for characterizing
solid electrode surfaces are surface stress–surface charge coefficient and potential–
surface elastic strain coefficient which are theoretically equivalent to each other. The
above two coefficients measured separately by several methods for a (111)-textured
Au (111) thin-film electrode in perchloric acid solution are compared, and the equality
of both coefficients is confirmed experimentally. Furthermore, the sign-reversals of
the above coefficients observed for nano-porous or (111)-textured Pt electrodes in
acid solutions are explained and the causes of the sign-reversal are discussed on the
basis of the changes in electronic structure of the electrode surfaces.
Keywords Surface stress · Surface reconstruction · Adsorption · Surface
stress–surface charge density coefficient · Potential–surface elastic strain
coefficient
3.1 Introduction
Potential- or adsorbate-induced changes in surface stress associated with surface
reconstruction or adsorption of electrolyte species on a solid electrode are typical
examples of the electro-chemo-mechanical properties. The changes in surface stress
of single-crystal Au electrodes for surface reconstruction or adsorption of electrolyte
anions have been measured as function of applied potential or surface charge density
by a cantilever bending method. On the other hand, the concomitant changes in
surface tension of single-crystal Au electrodes can be estimated by using the Lippmann equation from the measurement of differential capacity or surface charge
density. In the present chapter, we compare the surface stress versus potential curves
© Springer Nature Singapore Pte Ltd. 2020
M. Seo, Electro-Chemo-Mechanical Properties of Solid Electrode Surfaces,
https://doi.org/10.1007/978-981-15-7277-7_3
67