Abstract
AbstractThe intrinsic charge‐induced surface stress of Ni thin films during electrochemical reactions with an alkaline electrolyte is measured in situ. Surface stresses induced by H absorption/desorption, α‐Ni(OH)2 formation, capacitive double‐layer charging, the α‐ to β‐Ni(OH)2 transformation, and β‐Ni(OH)2/β‐NiOOH redox reactions are identified, and each provided additive contributions to the overall stress state. Surface stresses are magnified in high‐surface‐area nanoporous Ni because local stress‐relaxation mechanisms are restricted when compared to a smooth Ni film. Ni film reversible tensile/compressive surface stresses correlate with anodic/cathodic potential scanning but with an opposite trend to that of a less reactive Au film. Surface stresses in the Ni films are up to 40 times that of Au films and suggest the possibility of using controlled surface‐stress generation for electrochemical actuation.
Highlights
The measurement of electrode surface stresses induced by electrochemical processes at an electrode/electrolyte interface provides a method to probe the underlining atomistic processes and chemical changes related to charge transfer.[1]
In situ measurement of surface stress, even in complex cases, can resolve sufficient detail that specific reactions can be deconvoluted and isolated
We demonstrate that these surface stress effects can be enhanced by a nanoporous surface morphology, which may provide an opportunity for the development of electrochemical microactuators based on low cost transition metals.[3b, 7]
Summary
The measurement of electrode surface stresses induced by electrochemical processes at an electrode/electrolyte interface provides a method to probe the underlining atomistic processes and chemical changes related to charge transfer.[1]. The intrinsic charge-induced surface stress of Ni thin films during electrochemical reactions with an alkaline electrolyte is measured in situ.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have