Electrocatalysis phenols

Kawagoe KF, Johnson DC. Electrocatalysis of anodic oxygen-transfer reactions. Oxidation of phenol and benzene at bismuth-doped lead dioxide electrodes in acidic solutions. J Electrochem Soc 1994 141 3404—3409. 

The section presented some information about the Sn02 electrode and rare-earth doped Sn02 electrode on the electrochemical phenol degradation process, and should be helpful for the application of electrocatalysis in the field of environment as well as for the preparation of electrocatalytic anodes. 

A composite biomaterial formed by Pd metal, carbon-ceramic mixture and oxidoreductase enz3ones constitutes a new t3rpe of renewable smface biosensor with a controllable size reaction layer [198]. The carbon provides the electrical conductivity, the enzymes are used for biocatalyst process, metallic palladimn is used for electrocatalysis of biochemical reaction product and the porous silica provides a rigid skeleton. The hydrophobicity of this composite material allows only a limited section of the electrode to be wetted by the aqueous analyte, thus providing a controlled thickness reactive layer. Another biocomposite material containing enzyme-modifled boron-doped diamond was used in the development of biosensors for the determination of phenol derivatives [199], alcohol [200] and glucose [201]. 

There are many substances which would appear to be good candidates for LC-EC from a thermodynamic point of view but which do not behave well due to kinetic limitations. Johnson and co-workers at Iowa State University used some fundamental ideas about electrocatalysis to revolutionize the determination of carbohydrates, nearly intractable substances which do not readily lend themselves to ultraviolet absorption (LC-UV), fluorescence (LC-F), or traditional DC amperometry (LC-EC) [2], At the time that this work began, the EC of carbohydrates was more or less relegated to refractive index detection (LC-RI) of microgram amounts. The importance of polysaccharides and glycoproteins, as well as traditional sugars, has focused a lot of attention on pulsed electrochemical detection (FED) methodology. The detection limits are not competitive with DC amperometry of more easily oxidized substances such as phenols and aromatic amines however, they are far superior to optical detection approaches. 

Reports on the use of monomeric MPc complexes for the electrocatalysis of phenols are rare, hence the use of some polymeric MPc complexes will be included in this section. Biosensors based on enzymes have been developed for many electrochemical analyses. The use of MPc complexes as part of the enzyme improves the sensitivities of the biosensors. Ozsoz et al. used CoPc monomer dispersed in mushroom tissue electrode as a catalyst for the analysis of phenolic compounds The enzymatic reaction between mushroom and the phenolic compounds was coupled with the catalytic activity of CoPc. The CoPc dispersed electrodes gave shorter response times and lower potentials compared to conventional tissue biosensors . 

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