| 摘要 |
Single frame porous catalyst electrodes, for use in the electrochemical decomposition of gaseous or liquid fuels in fuel cells, hydrogen separation in electrolysis cells, e.g. from aqueous alkali solutions using nickel electrodes, KC103 electrolysis and in amalgam-hydrogen elements, are produced by mixing, preferably under mechanical pressure, one or more metal powders which are to form the electrode with one or more metal powders which are soluble in alkaline or acidic solution, pressing the powder mixture into shape and then sintering or simultaneously shaping under pressure and sintering, and treating the shaped article with alkaline or acidic solution in which the first metal or metals are insoluble to dissolve out the second metal or metals. Preferably the powder mixture consists of by weight 30-95% of the first metal or metals and 5-70% of the second metal or metals, and sintering is effected at 350-800 DEG C. The shaped powder metal, which may be provided with a sheet, sieve or mesh metal backing, may be presintered below the sintering temperature, preferably in a plurality of stages of increasing temperature, prior to sintering. For example, a porous nickel electrode is made by mixing a powdered mixture of 32% Ni and 68% Al of particle size 10-40 micron in a pressure-mixing device, shaping under pressure, placing the shaped piece on a nickel support in a hydrogen atmosphere and pre-sintering at between 350 and 450 DEG C., and sintering at 460-600 DEG C., prior to treating with KOH solution to which may be added tartaric acid. For alkaline electrolytes, the first metal may be Ni, Cd, Ag, Pt, Ir, Rh and/or Pd, and the second metal Al, Zn, Mg, W, Mo and/or Fe. For acidic or neutral electrolytes the first metal may be Pb, Pd, Pt, Ir, Rh, Ti, Ta and/or Cr, and the second metal Al, Zn, Mg, Ni, Ag, Cu or Fe. |
