Temperature-controlled growth of micro- and nanocrystals on the surface of NiO+CuO/TiO2/Ti composites

Methods for Controlling the Surface Architecture of Coatings Formed by Plasma Electrolytic Oxidation

“…The composition of crystals growing on the surface of NiO+CuO/TiO2/Ti composites formed by a combination of PEO and impregnation strongly depends on the annealing temperature [29]: CuO crystals are formed after annealing at 500-700°C, NiWO4 crystals -at 750-850°C, and Ni2.62Ti0.69O4 whiskers -at ≥900°C. The data obtained indicate that the electrolyte residues and the impregnating solution accumulated on the surface and in the pores of the coatings, as well as the diffusion of titanium from the depth of the coating to the surface play an important role in the formation of microand nanocrystals.…”