Electrochemistry of chemisorbed molecules. I. Reactants connected to electrodes through olefinic substituents

Abstract

The tendency of olefins to chemisorb irreversibly on platinum electrodes is exploited to attach a variety of reactive entities to the electrode surface. Chelates connected to the electrode surface through an olefinic side chain allow metals to be selectively chemisorbed at the electrode surface. The stability of the chemisorbed metal complex is shown to vary with electrode potential, due to the influence of the electrical double layer, in such a way that the chelating ability of the chemisorbed chelate can effectively be "switched" on or off. Studies of the electrode reactions of chemisorbed complexes of Fe and Pt and of organic depolarizers such as substituted polyhydric phenols indicate that only in certain instances are the adsorbed reactants able to achieve a reactive orientation of the sort acquired readily by dissolved species. Evidence is presented that the system of each adsorbed olefin studied undergoes ten-electron oxidation to form the corresponding carboxylic acid and/or CO2. Equations which describe the electrochemistry of chemisorbed molecules are derived and tested.

Shape‐Switchable Azo‐Macrocycles

“…Chemically modified surfaces were already the subject of many studies in the last decades since they find application in numerous areas including electrocatalysis, [114] [115] corrosion protection, [116] molecular electronics, [117] [118] integrated circuits, [119] [120] information storage, [120]- [122] sensing [123] [124] and many others.…”

“…[226]- [229] It has been successfully applied in numerous areas ranging from corrosion protection of bulk surfaces [116] to the integration of selective functionalities in nano sensing devices. [119][122] [120] For electronic applications the modification of conducting surfaces at the molecular level with functional active building blocks represents a promising approach to new electrodes with tailor made surface chemistry.…”

Permselective Properties of Electropolymerized Guaiacol Derivatives

“…This parameter is governed by size of the monomer molecules and specific interactions with the electrode support. As seen, guaiacol (not substituted)and 6 gave higher peak charge values than the others with the exception for 2 which exhibited the highest value probably because of well-known ability of allyl compounds to undergo adsorption on platinum [12]. This assertion can be supported by the observation that negligible difference in the polymerization charge is observed between 2, 3, and 4 compounds on glassy carbon electrodes.…”

Characterization of Tris (5-amino-1,10-phenanthroline) Ruthenium(II/III) Polymer Films Using Cyclic Voltammetry and Rutherford Backscattering Spectrometry

“…In each of these examples, the electrodes function to catalyze electrochemical reactions, improve electrode stability, and help develop electrochemical sensors and biosensors. Since the work done by Lane and Hubbard (Lane et al, 1973) involving the use of chemisorbed metals on platinum electrode surfaces, numerous methods have been developed to anchor compounds on various electrode materials. Some of the different methods of compound immobilization and electrode functionalization include spin coating, covalent attachment, and electropolymerization (Brown et al, 2002).…”