Over the past few years, considerable effort has been devoted to the development of new energy storage devices with high power and energy density to substitute Lithium-based batteries, because the predicted high demand associated with many large-scale applications has generated serious concerns regarding the safety and sustainability of metallic Li.[1] In particular, Mg ion battery (MIB) has been regarded as the most promising candidate because of its ‘green’ character, high natural abundance in the Earth’s crust (13.9% as compared to 7*10^-4 % for Li), and chemical stability.[2] In comparison with Li, Mg is inherently much safer due to its air stable and free of dendritic formation during electrochemical cycling,[3] the latter feature could enable Mg has a theoretical volumetric capacity of 3833 mAh/cm³, nearly twice as that of Li, 2061 mAh/cm³, indicating the good potential of MIB to reach a high volumetric energy density.[4,5] However, it is still in high demand to find the electrode materials that unites with metallic Mg and fulfills requirements such as high specific capacity, power density, rate performance and good recyclability.[2,6,7]

Here, we report two novel electrode materials, Mn₃O₄ nanoparticles with high specific surface area (102.4 m²/g) and graphene nanosheets. The studies of Mg-battery performances were carried out in a standard coin cell which the synthesized materials as cathode (or anode), magnesium ribbon as anode (or cathode), glass fiber as separator and (PhMgCl)₂-AlCl₃/THF as electrolyte. The electrochemical performance was evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge-discharge techniques.

References:

[1] L. G. Lu, X. B. Han, J. Q. Li, J. F. Hua and M. G. Ouyang, J. Power Sources, 2013, 226, 272.

[2] E. Levi, Y .Gofer and D. Aurbach, Chem. Mater., 2010, 22, 860.

[3] J. O. Besenhard and M. Winter, ChemPhysChem, 2002, 3, 155.

[4] M. Matsui, J. Power Sources, 2011, 196, 7048.

[5] C. Ling, D. Banerjee and M. Matsui, Electrochim. Acta, 2012, 76, 270.

[6] H. D. Yoo, I. Shterenberg, Y. Gofer, G. Gershinsky, N. Pour and D. Aurbach, Energy Environ. Sci., 2013, 6, 2265.

[7] I. Shterenberg, M. Salama, Y. Gofer, E. Levi and D. Aurbach, MRS Bull., 2014, 39, 453.