Magnesium Anode Pretreatment Using a Titanium Complex for Magnesium Battery

Abstract

Although magnesium batteries have received a great deal of attention as a promising power source, the native oxide layer on the Mg surface significantly impedes practical applications, because of the sluggish kinetic behavior of Mg-ion deposition and dissolution. Here, a new approach to improve electrochemical reactivity of Mg anode is proposed, based on chemical pretreatment of the Mg anode using a titanium complex, Ti(TFSI)(2)Cl-2, that effectively removes the native oxide layer on the Mg anode surface. The pretreatment of the Mg anode by Ti(TFSI)(2)Cl-2 remarkably decreases the binding affinity between Mg and O via the formation of a multicoordinate complex (Mg-O-Ti). Thereafter, a series of chemical reactions cleave the Mg-O bonds, resulting in a fresh Mg surface. This creates a cell comprised of the Ti(TFSI)(2)Cl-2-pretreated Mg anode, glyme-based electrolytes, and cathode material that exhibits reversible electrochemical behavior at the electrode/electrolyte interface, resulting in practical applicability and good electrochemical performance.