Non-equilibrium growth patterns and oscillations during electrochemical deposition of Zn-Cu binary system in batch and flow reactors

Department of Chemistry, DDU Gorakhpur University, Gorakhpur-273 009, Uttar Pradesh, India

E-mail : ishwar_das@rediffmail.com

Department of Chemistry, St. Andrews College, Gorakhpur-273 001, Uttar Pradesh, India

Manuscript received 2 July 2008, revised 15 July 2009, accepted 21 August 2009

Growth patterns of Zn-Cu alloys in the ɳ and β phases have been developed and examined. Patterns become more compact and dense on Increasing the copper content and field Intensity. The compactness is more in the p phase than those in the β phase. Fractal dimension· D was computed In each case by box counting method. Weight or aggregates at different concentrations of CuSO₄ was determined. Electrodeposited aggregates were characterized by X-ray diffraction (XRD) study. Electrodeposition or metals under the diffusion limited conditions shows spontaneous potential oscillations. Cathode potential was measured as a function or time during electrochemical deposition of Zn, Cu and Zn-Cu alloys in batch and In a Continuously Stirred Tank Reactors (CSTR). The morphology, amplitude and frequency of oscillation were found to depend on the copper content. A transition from biperiodicity to periodic oscillation was observed when copper sulphate was introduced In ZnSO₄ solution.