Electrocapillary Metal Expulsion in Ga–Bi–Sn–Pb Liquid Alloy System

Abstract

Electrocapillary metal expulsion has recently emerged as a promising low-temperature approach for separating metals from liquid alloys. However, prior studies have been largely limited to binary and ternary systems in aqueous electrolytes, where selectivity is primarily governed by intrinsic surface-energy differences of the constituent solute metals. Here, we extend this framework to a multicomponent quaternary Ga–Bi–Sn–Pb liquid alloy and demonstrate that electrolyte composition provides an additional parameter for controlling expulsion behavior. Under cathodic polarization of the liquid metal–electrolyte interface, electrocapillary charging reduces interfacial tension and promotes surface..