Ionic Transport in Potential Coating Materials for Mg Batteries
; Chem. Mater. 31, 8087–8099 (2019).
BibTeX
@article{Chen2019ionic,
author = {Chen, T. and Gautam, G. S. and Canepa, P.},
title = {{Ionic Transport in Potential Coating Materials for Mg Batteries}},
journal = {Chemistry of Materials},
volume = {31},
pages = {8087--8099},
year = {2019},
doi = {10.1021/acs.chemmater.9b02692}
}Brief summary
Coatings could protect the electrodes of magnesium batteries from the electrolyte, but they must let magnesium ions through quickly. Computing how easily magnesium moves through about 27 compounds, we identify MgSiN2, MgI2, MgBr2, MgSe and MgS as coatings for the magnesium anode, and MgAl2O4 and Mg(PO3)2 for oxide cathodes up to about 3 V.
Full abstract
A major bottleneck for the development of Mg batteries is the identification of liquid electrolytes that are simultaneously compatible with the Mg-metal anode and high-voltage cathodes. One strategy to widen the stability windows of current nonaqueous electrolytes is to introduce protective coating materials at the electrodes, where coating materials are required to exhibit swift Mg transport. In this work, we use a combination of first-principles calculations and ion-transport theory to evaluate the migration barriers for nearly 27 Mg-containing binary, ternary, and quaternary compounds spanning a wide chemical space. Combining mobility, electronic band gaps, and stability requirements, we identify MgSiN2, MgI2, MgBr2, MgSe, and MgS as potential coating materials against the highly reductive Mg metal anode, and we find MgAl2O4, and Mg(PO3)2 to be promising materials against high-voltage oxide cathodes (up to ∼3 V).