Gold electrocatalyst, methods for preparing it, electrodes prepa

Details Gold electrocatalyst, methods for preparing it, electrodes prepa Gold electrocatalyst, methods for preparing it, electrodes prepa

1989-11-13

1991-08-20

Niebling, John F.

Chemistry: electrical and wave energy

Processes and products

204 98, 204101, 204290R, 204292, 204294, 204284, 429 27, 429 44, C25B 100, C25B 1108

Patent

active

050411950

ABSTRACT:
The disclosed electrocatalyst material is useful in electrodes, especially in cathodes for the reduction of oxygen or peroxide to water or hydroxide. The electrocatalyst typically comprises 0.1 to 20 weight-%, based on the weight of the material, of a supported particulate elemental gold wherein the particles are apparently crystalline in nature, apparently with exposed (100) faces, but smaller in size than 5 nanometers (<50.ANG.). These tiny monocrystals of gold are supported on carbon back or particulate conductive ceramic-like compounds having a B.E.T. surface area of at least 50 m.sup.2 /g. The supported gold monocrystals appear to be selective for the reductions described above, and performance in air- or O.sub.2 -cathodes is outstanding, e.g. >0.7 volt vs. RHE at 200 mA/cm.sup.2, generally indicating a substantial proportion of four-electron change reactions when oxygen is being reduced. The electrodes (which are also useful as anodes in acid electrolytes) are made by impregnating the support material with a reducible gold compound dissolved in a polar solvent, gently evaporating the solvent, and chemically reducing the gold compound in situ at a moderate temperature with a flowing reducing gas (e.g. H.sub.2), then applying the resulting supported gold to a porous backing material. Typical gold content levels at the electrode surface are <2 mg/cm.sup.2. Cathodes of this invention are useful in various types of air or oxygen-depolarized cells, alkaline fuel cells, metal/air c

REFERENCES:
patent: 3239382 (1966-03-01), Thompson
patent: 3467554 (1969-09-01), Forten et al.
patent: 3506494 (1970-04-01), Adlhart
patent: 3510355 (1970-05-01), Fishman
patent: 3668014 (1972-06-01), Katsoulis
patent: 3701687 (1972-10-01), Grubb et al.
patent: 3776776 (1973-12-01), Petrow
patent: 4111842 (1978-09-01), van Montfoort et al.
patent: 4127468 (1978-11-01), Alfenaar et al.
patent: 4221644 (1980-09-01), LaBarre
patent: 4317704 (1982-03-01), McIntyre et al.
patent: 4407905 (1983-10-01), Takeuchi et al.
patent: 4407906 (1983-10-01), Stonehart
patent: 4440617 (1984-04-01), Solomon
patent: 4454649 (1984-06-01), Jalan et al.
patent: 4456521 (1984-06-01), Solomon
patent: 4457986 (1984-07-01), Bindra et al.
patent: 4461814 (1984-07-01), Klinedinst
patent: 4481303 (1984-11-01), McIntyre et al.
patent: 4614692 (1986-09-01), Kajiyama et al.
patent: 4615954 (1986-10-01), Solomon
patent: 4711829 (1987-12-01), Luczak et al.
Turkevich, J., Gold Bull. 18, 86-91, 125-131 (1985).
Ehrburger, P., Advances Colloid Interf. Sci. 21, 275-302 (1984).
Kinoshita, K., Chapter 8, "Small-Particle Effects and Structural Consideration for Electrocatalysis" in: Modern Aspects of Electrodensity, No. 14, Ed. Bockris et al., N.Y., pp. 557-637.
Yeager, E., NBS Special Cub. 455, pp. 203-219 (1976).
Markovic, N. M. et al, J. Electroanal. Chem., 165, 121-133 (1984).
Adzic, R. R. et al, J. Electroanal. Chem. 165, 105-120 (1984).
Adzic, R. R. et al, J. Electroanal. Chem. 138, 443-447 (1982).
J. Singer et al, "Evaluation Parcemeters for Alkaline Fuel Cell Oxygen Electrode", NASA Technical Memorandum 87155 (Nov. 1985).
McIntyre, J. D. E. et al, "Electrochemistry at Single-Crystal Metal Electrodes. Electrocatalytic Effects of Surface Atomic Structure, Defects and Adatoms on Oxygen Reduction", in: Electrochemistry and Physics of Electrocatalysis, Ed., Weaver et al, The Electrochemical Society, PV 84-12, pp. 102-129.
V. Jalan et al, J. Electrochem. Soc., 130, 2299-2302 (1983).

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