The effect of complexing agents on the oriented growth of electrodeposited microcrystalline cuprous oxide film

Three conventional complexing agents, including lactic acid, citric acid and EDTA, are applied in the electrodeposition of microcrystalline cuprous oxide (Cu2O) film on indium tin oxide glass substrate. Both scanning electron microscopy and X-ray diffraction have been performed to characterize the morphology and texture of microcrystalline Cu2O film. It is found that the stability constant of copper-based complex compound can obviously influence the deposition overpotential of Cu2O, and the overpotential can significantly alter the growth priority of different planes, which results in oriented growth of Cu2O grains. The quantitative relationships between the stability constant and the deposition overpotential of different complexing agents, as well as the relationship between the overpotential and the formation energy of microcrystalline cuprous oxide's (1 1 0), (1 1 1) and (2 0 0) planes are calculated, respectively. (C) 2012 Elsevier Ltd. All rights reserved.