Increasing the Interfacial Reducing Species for Ultrafast Leaching of Spent Cathodes via Suppressing Aggregation

ABSTRACT Modulating the reductive environment of the leaching system is pivotal to the recovery of critical metals from spent batteries. However, hydrometallurgical processes, especially organic acids‐based systems, are plagued by the self‐aggregation of reducing species, which impairs their capacity to engage in interfacial reactions. Herein, an aggregation inhibition strategy by controlling intermolecular interactions within the solvent microenvironment is proposed, which enhances the mass transfer efficiency of reducing species, thereby accelerating the interfacial reaction kinetics. Based on this, the developed betaine hydrochloride‐citric acid‐ethylene glycol (BCE) ternary system achieves complete leaching of metals within 20 min, exhibiting a 30‑fold increase in reaction kinetics relative to conventional processes. Notably, ethylene glycol (EG) serves as both an aggregation inhibitor and a microwave‐responsive medium, simultaneously suppressing citric acid (CA) self‐aggregation and boosting their interfacial reaction efficiency. This work provides not only a practical route for efficient battery recycling but also a generalizable design paradigm for tailoring multiphase reaction environments through solvent engineering.