| 摘要 |
Platinum and iridium in catalytic electrodes for electrochemical uses is partially replaced with lead ruthenate-tantalum oxide composite. Electrodes are fabricated by first coating a film-forming metal substrate with a platinum-iridium composite undercoat, then overcoating with a composite containing lead, ruthenium, tantalum, platinum, iridium and oxygen. The most preferred anodes have a titanium substrate initially coated with approximately at least 2 gm/m2 of 70:30 w/o Pt:Ir composite, followed by about 20 gm/m2 of a composite having the nominal composition of 22.2w/o Pb2Ru2O6; 66.6 w/o Ta2O5; 7.9 w/o Pt and 3.4 w/o Ir. The outer layer of the prepared anode contains from about 10 to about 16 w/o lead, from about 40 to about 65 w/o tantalum, from about 5 to about 7.5 w/o ruthenium, from about 6.0 to about 10 w/o platinum, from about 2.5 to about 5 w/o iridium, and from about 10 to about 20 w/o oxygen. These electrodes may be used in acidic, neutral or alkaline solutions. Typical uses include production of chlorine and chlorine compounds and electrowinning of metals, such as zinc.
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