Electrode films of porous agarose: The effects of physical structure on electron transport processes. [Impregnated with Nafion; immobilized electroactive species]
Potential use of chemically modified electrodes in electrocatalysis has stimulated interest in creation and characterization of electrode films for reagent immobilization. We have created two highly porous electrocatalyst support matrices, with high rates of electron transport. Both are based on immobilization of reagents in agarose gel. In one case, Nafion was impregnated into agarose gel films. Diffusion of methyl viologen in Nafionagarose matrices are higher than in Nafion. In Nafion, the diffusion coefficient decreases with increasing methyl viologen concentration, while in Nafionagarose, the opposite dependence is observed. The faster rate of electron transport in Nafionagarose films is related to the heterogeneous structure and the coupling of the diffusion pathways. In the second application of agarose gels as an electrode coating material, agarose hydroxyl groups were activated in 1,1'carbonyldiimidazole and subsequently reacted with amine derivatives of electroactive mediators. Electron transport between the electroactive sites in the gel is very rapid (on the order of 10/sup -7/ cm/sup 2/s. Interpreting the data in light of the Dahms-Ruff description of electron transport shows that the rate of electron transport through both ferrocene and viologen derivatized gels is limited by the rate of electron self-exchange of the species. 22 figs., 15 tabs
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 5250762
- Report Number(s):
- LBL-24822; ON: DE88007366
- Country of Publication:
- United States
- Language:
- English
Similar Records
Electrocatalytic reduction of nitrate and nitrite at Nafion-coated electrodes in concentrated sodium hydroxide solution
Removal of digoxin from plasma using monoclonal anti-digoxin antibodies immobilized on agarose
Related Subjects
300503 -- Fuel Cells-- Materials
Components
& Auxiliaries
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400400* -- Electrochemistry
AZINES
BIPYRIDINES
CARBOHYDRATES
CATALYST SUPPORTS
CATALYSTS
COLLOIDS
DISPERSIONS
ELECTROCATALYSTS
ELECTRODES
ELECTRON TRANSFER
FILMS
GELS
HETEROCYCLIC COMPOUNDS
MATERIALS
MODIFICATIONS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
POLYSACCHARIDES
POROUS MATERIALS
PYRIDINES
SACCHARIDES
SURFACES