DFT ANALYSIS OF INTERFACIAL PROCESSES OCCURRING IN THE FIRST STEPS OFELECTRODEPOSITION OF NICKEL FROM CHLORIDE MELT

In this work, we have studied the cathodic reduction of Ni(II), dissol ved in the LiCl-KCl eutectic melt, at a nickel cathode. The structure of LiCl-KCl melts has been previously determined, and in applying DFT calculations performed with DMol and DGauss, we were able to determine (1) the nature of the Ni(II) solvated species (2) the corresponding e quilibrium chloride exchange reactions, as well as (3) the cation infl uence on these species and equilibria. Geometrical considerations and orbital shapes of the Ni(II) entities allowed us to find the most like ly species to approach the cathode: KNiCl3. The nickel cathode was sim ply modellized as a monoatomic planar surface composed of 36 Ni atoms. The interaction between the cathode and KNiCl3 complex has been then investigated. Electron density contour maps show the role played by ch lorine atoms in the Ni adsorption process. (C) 1997 Elsevier Science B .V.