Simultaneous Suppression of Metal Corrosion and Electrolyte Decomposition by Graphene Oxide Protective Coating in Magnesium-Ion Batteries: Toward a 4-V-Wide Potential Window

Despite remarkable developments in electrolyte systems over the past decades, magnesium-ion batteries still suffer from corrosion susceptibility and low anodic limits. Herein we describe how graphene oxide (GO), coated onto non-noble metals (Al, Cu, and stainless steel) via- electrophoretic deposition, can solve this problem. In all phenyl complex electrolytes, GO coating results in a significant suppression of corrosion and extends the anodic limits' (up to 4.0 V vs Mg/Mg2+) with no impact on reversible Mg plating/stripping reactions. The same effect of GO coating is also established in magnesium aluminum chloride complex electrolytes. This remarkable-improvement is associated with the electtostatic interaction between the ionic charges of electrolytes and the-surface-functional groups of GO: In addition, GO coating, does not aggravate the cathode performance of Mo6S8, which allows the use of non-noble metals as current collectors. We also discuss, the role of GO in. increasing anodic limits when it is hybridized with alpha-MnO2.