JOURNAL OF APPLIED ELECTROCHEMISTRY 7 (1977) 331-337 Formation of powdered copper deposits by square-wave pulsating overpotential K. I. POPOV, M. D. MAKSIMOVI~, M. G. PAVLOVIC, G. R. OSTOJIC Faculty of Technology and Metallurgy, Universityof Beograd, Beograd, Yugoslavia Received 15 November 1976 Copper powder deposits were obtained by square-wave pulsating overpotential electrolysis and by constant overpotential electrolysis. It is shown that the particle grain size and the morphology of deposited powders are functions of amplitude overpotential, frequency of pulsati6n and pulse to pause ratio in pulsating potential deposition, and of overpotential in constant overpotential deposition. 1. Introduction In a recent paper [1] it was shown that powdered copper deposits with controlled grain sizecan be obtained in constant and sinusoidal pulsating overpotential deposition. It was shown that morphology and particle grain size are functions of overpotential in constant overpotential elec- trolysis, while in the case of sinusoidal pulsating overpotential these parameters were functions of amplitude overpotential and frequency of pulsation. Similar effects can be expected in square-wave pulsating overpotential electrodeposition. In this case, besides the amplitude of the overpotential and frequency of pulsation, the pulse to pause ratio can also be varied. It was the purpose of this work to investigate the effect of these parameters in the square-wave pulsating overpotential deposition of powder on powder morphology and particle grain size. 2 < g ~A Fig. 1. The shape of the input pulsating overpotential. Printed in Great Britain. 9 1977 Chapman and Hall Ltd. ELECTRODE SURFACE AREA -O.BI cm2 T i - - PULSEDURATION Tp-- PAUSE DURATION I A - - OVERPOTENTIALAMPLITUDE Tp TIME, t 331