Periodically changing rate

MaksimoviC, M. D. Theory of the Effect of Electrodeposition at a Periodically Changing Rate on the Morphology of Metal Deposits 19... 

Periodically Changing Rate on the Morphology of Metal Deposits... 

This work was supported by the Ministry of Sciences, Technologies and Development of the Republic of Serbia under the research projects Electrodeposition of Metal Powders at a Constant and at a Periodically Changing Rate 1806/2002) and Surface Science and Thin Films (2018/2002). 

K. I. Popov and M. D. Maksimovic, Theory of the effect of electrodeposition at periodically changing rate on the morphology of metal deposition, in Modem Aspects of Electrochemistry. Vol. 19, J. O M. Bockris and B. E. Conway, editors. Plenum Press, New York, 1989, pp. 193-250. 

In summary, deposition under nuxed activation-diffusion control causes the formation of a number of growth forms and the increase of surface coarseness, this increase being more pronounced at higher current densities. It should be noted that electrodeposition at a periodically changing rate can change considerably the morphology of the deposits [13, 25]. 

Electrodeposition with a periodically changing rate can be described in terms of time-and distance-dependent concentrations ... 

It was shown earlier that at sufficiently high frequencies, the average current density in electrodeposition at a periodically changing rate produces the same concentration distribution inside the diffusion layer as a constant current density of the same intensity. Hence, Eq. (4.76) is valid for all cases of electrodeposition at a constant and periodically changing rate at sufficiently high frequencies. 

Maksimovic MD (1995) The influence of the charge and discharge of the electrical double layer in electrodeposition by periodically changing rate. J Stab Chem Soc 60 449-458... 

Maksimovic MD, Popov KI (1999) Mass transfer during electrodeposition of metals at a periodically changing rate. J Serb Chem Soc 64 317-340... 

Bek RY, Kudryavtsev NT (1961) The effect of a periodically changing rate on the zinc electrodeposition from zincate alkaline solutions. Zh Prikl Khim 34 2020-2027 (in Russian)... 

Meanwhile, the macrostructure of the silver deposit produced at an overpotential of 1,000 mV was completely different than that of the copper electrodeposited at the same overpotential. As already mentioned, holes formed by attached hydrogen bubbles surrounded by cauliflower-like agglomerates of copper grains (the honeycomblike structure see other chapters) were formed by copper electrodeposition at an overpotential of 1,000 mV [7, 8, 10-13]. The copper powder obtained by tapping the powdered deposit consists of an aggregate of small cauliflower-like particles [14]. Similar copper structures were also observed by electrodeposition at periodically changing rate [15-20]. 

It is necessary to note that effects on morphology of powdered deposits similar to those obtained by the use of more solutions of different CUSO4 and H2SO4 concentrations can be attained by the use of the only one solution if electrodeposition processes were performed at a periodically changing rate. 

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