Zeolite-modified electrodes with analytical applications*

Pure and Applied Chemistry (Impact Factor: 2.49). 02/2011; 83(2):325-343. DOI: 10.1351/PAC-CON-10-07-08


Zeolite-modified electrodes (ZMEs) have been widely investigated because of their chemical, physical, and structural characteristics (shape, size, and charge selectivities; physical and chemical stabilities; high ion-exchange capacity; hydrophilic character; etc.), which make them of high interest in the design of electroanalytical systems. The paper presents recent literature data about fundamental and practical aspects related to the obtaining and applications of ZMEs. Some new ZMEs based on carbon paste incorporating soluble phenothiazinic dyes adsorbed on X-type zeolites are assessed comparatively, and the influence of some experimental parameters on the electrochemical response of these electrodes was investigated. The kinetic parameters for the heterogeneous electron-transfer process corresponding to the surface-immobilized mediators were determined, and all observed differences were used as evidence of the influence of the mediator structure and of the zeolite nature on the electrochemical activity of the new electrodes and on their electrocatalytic properties toward beta-nicotinamide adenine dinucleotide (NADH) or ascorbic acid (AA) electro-oxidation and H2O2 electroreduction.

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    • "Structuration of electrode surfaces with inorganic thin films has become a well-established field of interest, notably for applications in electroanalysis [1–21]. Various materials have been used for that purpose, including zeolites [2] [3] [4] [5], clays [6] [7] [8] [9] and layered double hydroxides [10] [11], silica [3] [12] [13] and silica-based organic–inorganic hybrids [13] [14], sol–gel materials [14] [15] [16] [17] and, more recently, ordered mesoporous materials [3,18–21]. The driving force to select one or another of these electrode modifiers often relies on the particular properties (ion exchange, selective recognition, hosting capacity, size selectivity, redox activity, permselectivity, etc.) which can be useful to the final application (preconcentration electroanalysis, electrocatalysis, permselective coatings, biosensors, . . "
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