Aluminum/zirconium alloys obtained by Al underpotential deposition onto Zr from low temperature AlCl3+NaCl molten salts

Abstract

Contrary to the widely accepted hypothesis that it is not possible, aluminum underpotential deposition (UPD) onto zirconium from a low temperature (200, 250 and 300 °C) equimolar chloroaluminate melt was recorded. Furthermore, it was shown that aluminum UPD facilitates alloy formation between the deposited aluminum monolayer and the zirconium substrate by interdiffusion. The aluminum/zirconium alloys formed at temperatures substantially lower than those needed for thermal preparation of the same alloys were Al3Zr2 and Al3Zr. The experimental techniques linear sweep voltammetry, potential step, scanning electron microscopy, energy dispersive spectroscopy and X-ray diffraction were used for the characterization of the obtained electrode surfaces.