DOI: 10.1021/acsenergylett.6c02064 ISSN: 2380-8195

Electronic Dipole-Driven Interfacial Stabilization for Corrosion-Resistant Magnesium Metal Batteries

Jinyoung Kim, Minkwan Kim, Heejin Kim, Jimin Lee, Naehyun Kang, Seonmo Yang, Seung Hyun Jeong, Ali Coskun, Jang Wook Choi

Abstract

Magnesium (Mg) metal batteries are promising next-generation energy storage platforms, but practical deployment is hindered by the morphological instability and corrosion of the Mg metal anode during high-rate operation or extended rest. Here, we modulate the electronic work function (Φ) of Mg metal by controlling the electronic dipole in methoxy-amine solvents. Specifically, in situ incorporation of indium cations (In3+) into the electrolyte creates an interfacial dipole that elevates the Mg surface work function, mitigating parasitic corrosion inherent to methoxy-amine electrolytes. Simultaneously, the magnesiophilic In layer induces uniform hexagonal Mg growth and suppresses dendrite evolution. This electronic and chemical synergy achieves a Coulombic efficiency exceeding 98.5% at practical current densities, an eightfold longer reversibility, and extended calendar life across multiple solvents. In full cells with Mo6S8 cathodes, the system sustains over 1000 coin- and 300 pouch-cell cycles at 1C, demonstrating that interfacial electronic and nucleation control enables unprecedented lifetime stability for multivalent batteries.