Silver cementation on copper in 1-butyl-3-methylimidazolium bromide-silver bromide ionic liquid medium

In this work the displacement deposition of silver onto copper substrate in solventless medium of 1-butyl-3-methylimidazolium bromide-silver bromide ionic liquid (BMImBr-AgBr) was studied. The Ag(I)/Cu cementation system in BMImBr-AgBr was investigated by means of electrochemical, gravimetric, optical, SEM and EDX methods. Experimental data showed that the deposition process of the nanosized porous layer of silver onto copper substrate proceeds by the two stages followed the first-order equation. Rate constants of K-1 = 5.1 x 10(-5) s(-1) and K-2 = 5.3 x 10(-4)s(-1) were calculated for the first and second stages, respectively. The cementation proceeded under the activation control of the anodic reaction rate. In stationary regime the control degree of anodic reaction was found to be 0.83. With usage of EIS method it was found that the transition from the first to the second stage of cementation is due to a decrease in the resistance of charge transfer in the anodic and cathodic reactions. We demonstrated that in solventless BMImBr-AgBr ionic liquid the nanosized porous silver layers with up to 10 pm thickness and good adhesion to copper substrate can be successfully obtained. (C) 2017 Elsevier B.V. All rights reserved.