National Research Council of Canada. Energy, Mining and Environment
Calculations; Crystalline materials; Diffusion; Electrolytes; Ionic conductivity; Lithium; Molecular dynamics; Potentiometric sensors; Crystalline phasis; First principles; First principles molecular dynamics; Large surface area; Molecular simulations; Site-to-site hopping; Solid-state electrolyte; Three orders of magnitude; Solid electrolytes
Recently it was found that nanoporous β-Li3PS4 (Liu et al., 2013), has an ionic conductivity three orders of magnitude higher than the two known crystalline phases. The exciting discovery has raised the optimism that this material may be a suitable candidate as solid state electrolyte. Here the lithium transport mechanisms in nanoporous and the crystalline phases were investigated with first-principles molecular dynamics calculations. The theoretical results reproduced the experimental trend. In all three systems the lithium migrations are found to be the similar through site-to-site hopping rather than free diffusion. The presence of vacant Li sites combined with the large surface area may be one of the reasons for the fast ionic conductivity in the nanoporous phase.
Computational Materials Science107 (6 June 2015): 134–138.