Copper–nickel codeposition as a model for mass-transfer characterization in copper–indium–selenium thin-film production

Abstract

The use of binary copper-nickel (Cu-Ni) codeposition from a complexing citrate electrolyte is proposed as a convenient model system for simple, rapid and inexpensive characterization of local mass-transfer limitations arising in the production of ternary copper-indiumselenium (CIS) thin films. Both the Cu-Ni and the CIS systems have been investigated in a small pilot cell and deposit thickness and composition distributions on a 5 9 5 cm 2 cathode have been compared. The experimental comparison confirms that the mass-transfer characteristics measured for copper deposition in the binary Cu-Ni codeposition system offer an excellent representation of the mass-transfer-limited deposition of copper and selenium in the ternary CIS system. The binary Cu-Ni system presents a number of advantages for process development, among which the possibility of operating at neutral pH and being much easier to handle, less expensive and less toxic than the CIS system. The results of the study presented here, although targeted to CIS production, may also be of use for the development of other electrodeposition processes in which one or more electro-active species are reduced under mass-transfer control.

Nanocrystalline Electroplated Cu–Ni: Metallic Thin Films with Enhanced Mechanical Properties and Tunable Magnetic Behavior

“…All Cu–Ni films were silvery‐bright and showed good adherence to the copper surface. Importantly, the films did not peel off from the substrate even at the highest overpotentials, a feature that is easily encountered in additive‐free baths due to the high tensile stress caused by hydrogen evolution 28. The measured film thickness was 3.0 ± 0.2 µm.…”

Electrodeposition of magnetic, superhydrophobic, non-stick, two-phase Cu–Ni foam films and their enhanced performance for hydrogen evolution reaction in alkaline water media

“…This phenomenon occurs because Cu is typically discharged under mass-transfer control, while Ni deposition is under chargetransfer control over a wide potential range. 40 When the agitation rate is sufficiently vigorous, Cu deposition governed by ion diffusion increases and the porous network is achieved, conrming the importance of Cu on the coating architecture.…”

“…The composition varies as a function of the applied current density, with the Ni content ranging from 15 at% to 60 at%, indicating that Ni electrodeposition is charge-transfer controlled. 40 Herein, the pore size together with the composition could be modulated to some extent. At low current densities (between −0.7 and −2 A cm −2 ) (see Fig.…”

Numerical simulation and experimental investigation of combinatorial electrodeposition of Ni‐Cu material library using modified Hull cell

“…Under these electrolytic composition conditions, Cu ions are reduced under mass transport (diffusion) control while Ni ions are reduced under charge transfer control during the codeposition of Ni‐Cu alloy thin films and is reported in many articles in the literature . It is also reported in the literature that partial current densities of Cu are very sensitive to the local hydrodynamic conditions when it deposits under mass transport control whereas Ni ions reduction is independent of the local hydrodynamic conditions . Therefore, the local changes in the hydrodynamic conditions in the vicinity of the electrode are responsible for the changes in the partial current densities of Cu which in turn results in the fluctuations in the composition of Cu most significantly in the Cu rich region of the material library i.e., before the intersection point.…”