Mesoporous Magnesium Manganese Silicate as a Cathode Material for Rechargeable Magnesium Batteries

Mesoporous magnesium manganese silicate as a cathode material for rechargeable magnesium batteries was prepared using mesoporous silica MCM-41 as both template and silicon source.X-ray diffraction(XRD),scan-ning electron microscope(SEM),transmission electron microscope(TEM) and N2 adsorption-desorption measure-ments were performed to characterize the mesoporous structure of the as-prepared material.Furthermore,the electro-chemical performance of mesoporous and bulk materials were compared by cyclic voltammetry and direct current charge-discharge measurements.The larger surface area of the mesoporous material favors the efficient contact be-tween active material and electrolyte,providing more active sites for the electrochemical reaction.As a result,the mesoporous material exhibits better electrochemical performance with lower polarization for magnesium de-intercalation and intercalation,larger discharge capacity and higher discharge flat plateau compared with corre-sponding bulk material.In 0.25 mol/L Mg(AlCl2EtBu)2/THF electrolyte,the initial discharge capacity and discharge voltage plateau of the mesoporous material can reach 241.8 mAh/g and 1.65V,respectively.The mesoporous struc-ture may provide a new approach to improve the reaction activity of the cathode materials for rechargeable magne-sium batteries.