Production and Structure of Electrocoatings Ni-P-TiO2-Al

Abstract

Composite Ni-P-TiO₂ and Ni-P-TiO₂-Al layers were prepared by simultaneous electrodeposition of nickel and titanium dioxide (anatase) with an addition of Al. powder on a copper substrate from a solution in which TiO₂ and Al powder were suspensed by stirring. The electrodeposition was carried out under galvanostatic conditions at a current density j = 300 mA cm⁻² and temperature of 298 K. The phase composition of the layers was investigated by the X-ray diffraction method. It was found that during the electrodeposition process a spherical crystalline particle of TiO₂ could be incorporated into the Ni-P phase matrix. The diffractogram of Ni-P-TiO₂-Al layer shows that the layer contains crystallites of aluminium and TiO₂. It means that transport of the metallic phase to the electrode is only possible when using TiO₂ as its carrier. This allows to extract of aluminium in alkaline environment from the Ni-P-TiO₂-Al layer and to obtain the active surface.