Texture and morphology of nickel coatings deposited in the presence of surfactants

Abstract

The morphology and orientation texture of nickel coatings obtained from a Watts electrolyte in the presence of iodine ions, butyne-2-diol 1,4, formalin and phthalic anhydride over a wide current density and temperature interval were investigated. Electron diffraction measurements made it possible to determine the orientation axis at small thicknesses (from 1000 to 10,000 Å).

The 〈110〉 and 〈211〉 orientation axes observed in coatings obtained in the presence of iodine ions appear at a considerably later stage of the formation process of the coatings, whereas the addition of butyne-2-diol 1,4 leads to the formation of an oriented coating at a coating thickness of 1000 Å.

The morphology of coatings with a 〈211〉 orientation in the presence of iodine ions and butyne-2-diol 1,4 is completely different owing to the different growth mechanisms in the presence of one or another of the additives.

The presence or absence of the extra reflection on the electron diffraction patterns from coatings with a 〈211〉 orientation is thought to be connected with a different growth mechanism and therefore with a different morphology.

In the presence of formalin or phthalic anhydride the morphology of the nickel coating closely resembles that observed in the presence of iodine ions in the electrolyte.