TY - THES T1 - Mechanics of electrified interfaces in diluted electrolytes A1 - Smetanin,Maxim Y1 - 2010/10/27 N2 - This work describes an experimental investigation of the interface between a solid metal and a fluid electrolyte. The question to be answered was: How does the surface stress vary with the surface charge density and how does the electrode potential vary with the elastic strain of the metal? The two variations are linked by the thermodynamic Maxwell relation that is well known but has not been tested in experiment. The aims of the thesis were twofold: First, to conduct careful experimental determination of the surface stress at electrode surfaces in aqueous electrolytes chosen to minimize the specific adsorption and thus to highlight selectively the role of capacitive processes. Second, to design and execute an experiment that allows for the first time to measure the variation of the electrode potential with the elastic strain. In the first approach, an in situ cantilever bending experiment was set up. The experiment shows that surface stress, f, varies linearly with the surface charge, q, with a response parameter ς = df/dq = —2.0 V. This value is larger, by the factor of two, than some previously reported experimental results. In the second approach, a new experimental approach was implemented, where the electrode is a metal film deposited on a polymer substrate and cyclic elastic strain of the electrode is imposed by straining the substrate via a piezoelectric actuator. This experiment supplies quantitative results for the potential — strain coupling. The value, ς = —1.83 V, is in good agreement with the cantilever bending experiment and the ab initio work. Therefore, for the first time, the important thermodynamic Maxwell relation was experimentally verified. KW - Elektrochemie KW - Elektrolyt KW - Grenzfläche KW - Elastische Spannung KW - Oberflächenspannung KW - Elektrodenspannung KW - Thermodynamik CY - Saarbrücken PB - Universitäts- und Landesbibliothek AD - Postfach 151141, 66041 Saarbrücken UR - http://scidok.sulb.uni-saarland.de/volltexte/2010/3380 ER -