Observation of the surface stress induced in microcantilevers by electrochemical redox processes

The potential-induced surface stress of a solid electrode was investigated in an electrochemical cell. Gold-coated atomic force microscopy microcantilevers were used as working electrodes to measure the current–potential response (by cyclic voltammetry) and simultaneous bending characteristics in solutions of NaNO3 and K3Fe(CN)6/NaNO3. The observed changes of differential surface stress at a microcantilever electrode were attributed to electrochemical-potential-induced changes in surface charge density, ion adsorption/desorption, and electron transfer across the electrode surface. The potential dependent change in stress shows promise for the study of microscopic properties at the solid–electrolyte interface.