Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown
Published: May 12, 2025
Abstract Aqueous rechargeable magnesium ion batteries promise high energy density and safety but suffer from low cycling stability poor reversibility, primarily due to side reactions passivation resulting the decomposition of free water. Here, study proposes a novel electrolyte composed cost‐effective MgCl 2 ∙6H O strong polar aprotic solvent (N,N‐dimethylformamide, DMF). The stronger interaction between Mg 2+ electronegative carbonyl oxygen in DMF induces transformation solvation structure original [Mg(H O) 6 ] (DMF) 3 Cl] + , thus decreasing coordination number ‐H 5.7 1.571 appropriately introducing Cl − inhibit hydrogen evolution (HER)/corrosion regulate layers. Furthermore, construction magnesiumophilic interface with HER over‐potential not only further suppresses reactivity active water also realizes stable under‐potential deposition (UPD) on Zn substrate. Consequently, symmetric cells substrate utilizing O‐DMF can consistently cycle for over 5200 h 80 mV at current 0.2 mA·cm −2 corresponding full exhibit discharge voltage that is 0.98 V higher than conventional aqueous systems.
Language: Английский