A Novel Route for Electrolytic Production of Very Branchy Copper Dendrites under Extreme Conditions

Abstract

Copper electrodeposition in a form of powder was examined using the pulsating overpotential (PO) regime from the sulfate electrolyte without or with an addition of various concentrations of chloride ions. Morphological and structural characteristics of the produced particles were analyzed by the scanning electron microscope (SEM) and the X-ray diffraction (XRD) method. The final morphology of Cu powders was determined with two parallel processes: a) suppression of hydrogen evolution reaction due to pause duration considerably longer than the deposition time, and b) catalytic effect of added chlorides. Depending on the amplitude of overpotential applied, addition of chlorides into the solution led to either an appearing of dendrites or to formation of verybranchy dendrites, what confirms a catalytic effect of these ions on the process of Cu electrolysis. The novel forms of copper dendrites, such as the needle-like and the 2D (two dimensional), were identified in this investigation, and the catalytic effect of chlorides on copper electrodeposition has been just discussed by morphological analysis of these dendritic forms. The XRD analysis of the copper dendrites obtained with an addition of chlorides showed predominantly oriented the Cu crystallites in (111) plane.