Anionic Effect
in Copper Plating from Sulfate Aqueous-Ethanolic Electrolyte Containing Cyclic Polyester
V. V. Kuznetsov, L. M. Skibina, S. V. Geshel’, I. N. Loskutnikova, and E. F. Kuznetsova
Rostov State University, Rostov-na-Donu, ul. Zorge 7, 344090 Russia
e-mail: Этот e-mail защищен от спам-ботов. Для его просмотра в вашем браузере должна быть включена поддержка Java-script
Received February 20, 2004
Abstract — It is shown that, in contrast to aqueous electrolytes, where the electrode process is promoted by the electroreduction of activated surface complexes of Cu2+ with S
anions, in aqueous-ethanolic electrolytes, it is promoted by sulfate complexes of copper(II) formed in the solution bulk and needing dissociation prior to the discharge. In the presence of cyclic polyester, the discharging complex species have to permeate through the barrier layer at the cathode surface. The layer consists of ethanol molecules and electroneutral associates of sulfate ions with Cu2+ cations containing crown-ester molecules in the coordination sphere. As a result, the electrode reaction is considerably inhibited with an increase in the concentration of S
anions (“anionic effect”), and tribotechnical characteristics of copper coatings are significantly improved.
anions, in aqueous-ethanolic electrolytes, it is promoted by sulfate complexes of copper(II) formed in the solution bulk and needing dissociation prior to the discharge. In the presence of cyclic polyester, the discharging complex species have to permeate through the barrier layer at the cathode surface. The layer consists of ethanol molecules and electroneutral associates of sulfate ions with Cu2+ cations containing crown-ester molecules in the coordination sphere. As a result, the electrode reaction is considerably inhibited with an increase in the concentration of S anions (“anionic effect”), and tribotechnical characteristics of copper coatings are significantly improved.