Understanding the role of Ca-doping onto MgMn2O4 cathode material for rechargeable Mg cells

MgMn 2 O 4 and MgMn 1.8 Ca 0.2 O 4 were synthesized by self-propagating combustion method and used as cathode materials for rechargeable magnesium ion cells. Their structural and morphological studies were evaluated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and Brunauer-Emmet-Teller theory (BET); the elemental distribution was determined using energy dispersive X-ray spectroscopy (EDX) and energy dispersive spectroscopy (EDS) mapping. Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were performed in order to determine electrochemical stability and properties of the prepared samples using 1 M of magnesium trifluoro-methanesulfonate (Mg(CF 3 SO 3 ) 2 ) in 1:1 volume of ethylene carbonate (EC) and 1,2-dimethoxyethane (DME). The galvanostatic charge–discharge test proved that MgMn 1.8 Ca 0.2 O 4 delivered the highest specific capacity of 60 mAh g −1 . Thus, this present work proved that MgMn 1.8 Ca 0.2 O 4 sample is a promising cathode candidate for magnesium ion cells. Graphical abstract