Charge transfer reactions, metal polymers

These reaction formulae indicate that the electron transfer taking place at the metal I polymer interface is accompanied by ionic charge transfer at the polymer Isolation interface, in order to maintain the electroneutrality within the polymer phase. Counterions usually enter the polymer phase, as shown above. However, less frequently the electroneutrality is established by the movement of co-ions present in the polymer phase, e.g., in so-called self-doped polymers. Oxidation reactions are often accompanied by deprotonation reactions, and H+ ions leave the film, removing the excess positive charge from the surface layer. It should also be mentioned that simultaneous electron and ion transfer is also typical of electrochemical insertion reactions however, this case is somewhat different since the ions do not have lattice places in the conducting polymers, and both cations and anions may be present in the polymer phase without any electrode reaction occurring. The es-... 

The electrochemical charge transfer reaction between the metallic substrate (Me, the electrode) and the polymer redox sites and... 

We consider the polymer to have a significant ion concentration. Thus an electrical double layer will form at the Me/poly interface, leading to capacitive charging current (mechanism a). Second, in dynamic measurements the current associated with the oxidation/reduc-tion of the polymer redox sites P /P (mechanism b) is often very large. Third, it should be noted that the reaction 0/R may proceed as a regular electrochemical charge transfer reaction at the metal/polymer interface. This was found to be the main mechanism in several systems, e.g., H2/H on polypyrrole-coated metal electrodes [235.246]. 

The polymers are synthesized by utilizing the Heck coupling reaction. Their structures are shown as polymers V to VII (Scheme 6). The metal-to-ligand charge transfer of the ruthenium complexes of polymer VI results in... 

Tetracyanoquinodimethane (TCNQ) and many of its derivatives are easily reduced to anions of the type TCNQ-, which form salts with various cations. With many cations, e.g., tetrathiafulvalene cations (TTF+), and N-methyl phenazinium cations (NMP+), the TCNQ- anions form electronically conducting salts (- molecular metals, -> charge-transfer complexes) that can be used as electrodes, especially because of their electrocatalytic properties (- biosensors, -> electrocatalysis, -> molecular metals) [i,ii]. TCNQ undergoes insertion electrochemical reactions (-> insertion electrochemistry) leading to TCNQ salts [iii, iv]. Polymers... 

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