Electrodeposition and characterization of Cu-TiO2 nanocomposite coatings

Cu-TiO2 nanocomposites were prepared by electrodeposition method onto copper substrate using an acid copper plating bath containing dispersed nanosized TiO2. The composition of codeposited TiO2 nanoparticles in the composite coatings was controlled by the addition of different concentrations of TiO2 nanoparticles in the bath solution. The average crystallite size was calculated by using X-ray diffraction analysis and it was similar to 32 nm for electrodeposited copper and similar to 33 nm for Cu-TiO2 composite coatings. The crystallite structure was fcc for electrodeposited copper and Cu-TiO2 nanocomposite coatings. The surface morphology and composition of the nanocomposites were examined by scanning electron microscopy and energy dispersive X-ray spectroscopy analysis. The effect of TiO2 content on the corrosion and wear resistance properties of the nanocomposite coatings was also presented. The codeposited TiO2 nanoparticles in the deposit increased the corrosion and wear resistance, which were closely related with TiO2 content in the nanocomposites. The wear resistance and microhardness of the Cu-TiO2 nanocomposite coatings were higher than electrodeposited copper. The corrosion resistance property of the electrodeposited copper and Cu-TiO2 nanocomposite coatings was evaluated by electrochemical impedance and Tafel polarization studies. Cu-TiO2 composite coatings were more corrosion resistant than electrodeposited copper.