Electroplating of iron from alkaline gluconate baths

Electroplating of iron onto copper substrates from non-polluting baths containing ferrous sulfate and sodium gluconate has been investigated under different bath composition, pH, temperature and current density conditions. A detailed study has been made on the influence of these parameters on potentiodynamic polarization curves, cathodic current efficiency and throwing power of the baths. The optimum plating bath has been found to be: 0.072 mol/l FeSO 4·7H 2O, 0.23 mol/l sodium gluconate, pH 12, current density of 0.167 A dm −2 and at 25 °C. This bath is characterized by an excellent throwing power. The surface morphology of the as-deposited iron was investigated by using scanning electron microscope (SEM) while the crystal structure was examined by using X-ray diffraction analysis.