2003 Volume 89 Issue 1 Pages 54-59
Continuous in-situ observations of changes in crystal orientation during zinc electrodeposition were performed using novel electrolysis cell that secure uniform current distribution through thin electrolyte layer.
It has been clarified that electrodeposition can be separated into the two regions. First one is epitaxial deposition region in which orientations of deposited zinc and substrate keep following relations; Fe(100)//Zn(10·1) Fe(110)//Zn(00·2), Fe(111)//Zn(00·2). This region continued until the thickness of the deposit became about 0.5μm.
Second one is bulk deposition region, in which the overpotential settled by electrolysis conditions determines the crystal orientation. Low overpotential leads to promoting Zn(00·2) deposition, and higher overpotential Zn(10·1) and Zn(11·0). Influences of the current density changes on the crystal orientation were also clarified. The use of an adsorbing organic additive influences both on the epitaxial growth region and on the bulk growth region and inhibits the deposition of the Zn basal plane.