MANUFACTURE OF LEAD DIOXIDE/TITANIUM COMPOSITE ELECTRODES

摘要

1476487 Lead dioxide/titanium electrodes BASF AG 4 Sept 1974 [5 Sept 1973 29 July 1974] 38595/74 Heading C7B A PbO 2 /Ti composite electrode, for an anode in a high current density cell, is made by anodic deposition of PbO 2 on an intermediate layer of a carbide or boride of Ti, Ta, Zr, Hf, V or Nb and/or a (di) silicide of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo or W and/or SiC applied to a Ti surface, e.g. by plasma or cathodic spraying, flame spraying, (chemical) vapour or electro-phoretic deposition. A carbide or boride may be applied by plasma spraying a powder thereof having a particle size of 15-90Á; or a layer 20-200Á thick and containing silicide and/or SiC modified with Fe, Ni, Co or a halide thereof may be applied. The Ti e.g. expanded mesh may be cleaned by sand or corundum blasting prior to coating. PbO 2 may be anodically deposited from a solution containing 1 to 25%Pb(II) nitrate or perchlorate, optionally up to 0À5%Cu(NO 3 ) 2 and up to 0À2% wetting agent based on ethoxylated alcohol, using a Cu sheet cathode at CD 1 to 10 A/dm2, the pH being maintained between 1 and 5 by adding PbCO 3 .