JPS6148591B

PURPOSE:To provide a cathode of low hydrogen overvoltage and long life by applying a composite plating layer consisting of fine conductive particles and silver or the 4th period VIII group metals on an electrode substrate. CONSTITUTION:A porous electrode substrate or flat plate electrode substrate consisting of conductive metals such as iron, copper and the like is heat-treated according to need, thereafter it is etched. Then, this etched electrode substrate is electroplated by using a both of silver, Ni, iron etc. suspended with fine conductive particles such as tungsten carbide. It this case, it is necessary to select plating conditions in such a manner that the fine conductive particles are contained at 2-30vol% in the plating layer. The fine conductive particles having 0.05-50mu grain sizes are used. The fine conductive particles disperse uniformly in the plating layer of the resultant cathode, and the surface of the plating layer forms a microporous layer with the fine conductive particles. Therefore, the effective area of the electrode surface is 10-20 times larger than that of the case in which no fine conductive particles exist, and the hydrogen overvoltage is lower.