Mild and Selective Alkahest-Enabled Electrochemical Extraction of Critical Elements from Ores

Direct recovery of elemental antimony (Sb) and bismuth (Bi) from sulfide ores under mild conditions remains a fundamental challenge. Binary sulfides, such as stibnite (Sb2S3) and bismuthinite (Bi2S3), are abundant mineral sources of critical elements, yet their extremely low solubility precludes conventional electrowinning. Here, we report the first acid-free, room-temperature method for selective electrowinning of Sb and Bi, enabled by a thiol–amine “alkahest” solvent that dissolves otherwise intractable sulfides. This approach enables electrochemical reduction to dense, nanoscale-uniform Sb films from natural ore, maintaining high selectivity against associated sulfides and gangue. The Faradaic efficiency is 80% with an energy consumption of 2.6 kWh/kg for Sb. The same strategy enables Bi electrowinning from bismuthinite and bismite (Bi2O3). These results establish a generalizable pathway for direct recovery of critical elements from sulfide and oxide ores and highlight alkahest solvents as a versatile platform for selective multielectron redox in complex solid–liquid systems.