  An atomistic study of the thermal properties of lithiated molybdenum
disulfide (MoS2) is presented and an explanation for the experimentally
determined anisotropic behavior of the in- and through-plane thermal
conductivity is proposed. Configurations with different levels of lithium
concentration are simulated using Density Functional Theory (DFT) and their
structural, electronic, and thermal transport properties are evaluated as a
function of the degree of lithiation. Comparisons between regular and
disordered lithium distributions as well as to the experimental data reveal
that the measured ratio of the in-plane to through-plane thermal conductivity
can only be reproduced if the disorder of the lithium ions is taken into
account. These results suggest that it is not only possible to modify the
thermal properties of MoS2 by changing the degree of lithiation, but also by
controlling its level of disorder.
