Electrodeposition of Al-Pt alloys using constant potential electrolysis in AlCl_3-NaCl-KCl molten salt containing PtCl_2

摘要

To form Al-Pt alloys for high temperature coatings, molten salt electrolysis was attempted with an AlCl_3-NaCl-KCl molten salt containing PtCl_2 at 448K. The voltammogram showed cathodic reduction of Pt ions to start at a potential of 1.4 vs. Al/Al(III) in the molten salt. Deposition of pure Pt was possible at 1.2V and there was co-deposition of Al and Pt at potentials more negative than 1.0V. The co-deposit was a mixture of intermetallic compounds of AlPt_2 or AlPt_3. The ratio of the Pt in the electrodeposits decreased with increasingly negative potentials from 100at.% at 1.2V to 25at.% at 0.0V.