Pulsed Galvanostatic and Potentiostatic Electrodeposition of Cu and Cu[sub 2]O Nanolayers from Alkaline Cu(II)-Citrate Solutions

Nanolayers of Cu and with a wide range of layer thicknesses have been produced using pulsed galvanostatic and potentiostatic electrodeposition from alkaline Cu(II)-citrate solutions. The thicknesses of the individual Cu and layers can be independently controlled and the composition of the multilayered materials, which also were studied using electrochemical quartz crystal microbalance, X-ray diffraction, and scanning electron microscopy, can be varied from pure Cu to pure by varying the current density or the deposition potential. It is shown that some of the deposited is reduced during the subsequent copper deposition step and that the influence of this effect depends on the Cu(II) concentration, the microstructure, and the deposition mode. Additional deposition is demonstrated to take place after the copper deposition step due to comproportionation and precipitation of . This effect facilitates electrodeposition of on Cu. Deposition of Cu on the layer formed by comproportionation and precipitation was likewise found to be more straightforward than on electrodeposited . Well-defined nanolayered materials are generally best manufactured using pulsed galvanostatic techniques because a much larger fraction of the was found to be reduced during the subsequent Cu deposition pulse in pulsed potentiostatic depositions.