Nanotechnology studies of layered fluoride superionic conductors

Abstract

A computer simulation by a molecular dynamics method at constant volume has been performed on a model material that is composed of accumulating two different fluoride conductors: · · · BaF 2 -CaF 2 -BaF 2 -CaF 2 · · · . The average value of CaF 2 and BaF 2 for the lattice constant of the new layered material is prepared to hold its mechanical strength. The CaF 2 region is compressed and the BaF 2 region is stretched along the c axis (z axis) in the thermal equilibrium state. It is obtained that the diffusion coefficient and ionic conductivity of F − ions in the layered fluoride conductors increases with decreasing periods, more specifically with the number of interfaces. The layer depth dependence on transport coefficients approximately coincides with the experiment.