Pulse electrochemical pathways regulation via dynamic interfacial control for selective lithium extraction from low-quality brines

The surging demand for lithium requires innovative technologies to sustainably extract lithium from low-quality brines, which are abundant but highly challenging due to low lithium content and high concentrations of competing ions. Inspired by biological ion transport rhythms, we present a bio-mimetic pulsed electrochemical strategy that enables dynamic interfacial regulation for selective and energy-efficient lithium extraction. By alternating between activation and relaxation phases, the pulsed system modulates local ion distributions, enhances lithium ion diffusion, and suppresses co-intercalation of Mg 2+ and Na + . Combined experimental investigations and COMSOL Multiphysics simulations reveal that pulse-driven interfacial dynamics alleviate concentration polarization and maintain high lithium selectivity, even in brines with extreme Mg/Li ratios (>120). Under optimized pulse voltage and duty cycle conditions, the system achieved a lithium–magnesium separation factor (α_Li/Mg) exceeding 9500, with a 91.6% reduction in energy consumption compared to conventional constant-voltage modes. Furthermore, we establish that the performance of pulsed electrochemical extraction is governed by a concentration–polarization–kinetics feedback mechanism, driven by the synergistic interplay of pulse voltage, current density, and duty cycle. This work establishes a membrane-free, tunable, and energy-adaptive lithium extraction system applicable to diverse saline resources.