パルス電解法によるパラジウムめっき

抄録

Electrodeposition of palladium from the baths of dinitrodiammine, dibromodiammine and dichlodiammine has been carried out by applying pulsed current electrolysis. Surface morphology, grain size, internal stress and texture of the palladium deposits, electrode potential during the electrodeposition and the hydrogen content of the deposits were examined as a function of pulse parameters. A close correlation was found between crystallographic features of the palladium deposits and the mode of pulse current. A decrease in the grain size of the deposits was observed in pulsed current electrolysis using higher pulse current density, longer pulse on-time, and shorter off-time, which lead to the highr cathodic overpotentials. Although the desorption of hydrogen from the palladium deposits was expected to occur during off-time, this did not always occur. The effect of pulse current electrolysis was most remarkable in dinitrodiammine bath, which yielded a palladium deposit containing less adsorbed hydrogen than that obtained by DC electrolysis.