In-plane thermal conductivity of disordered layered W Se2 and (W)x (W Se2) y superlattice films

It was recently reported that misoriented layered W Se2 and (W)x (W Se2) y films possess extremely low cross-plane thermal conductivity. Here, we report that the in-plane thermal conductivity results for W Se2 and W4 (W Se2) 10 films measured by using a suspended device are about 30 times higher than the cross-plane values because of the in-plane ordered and cross-plane disordered structures and about six times lower than that of compacted single-crystal W Se2 platelets. The additional W layers in the W4 (W Se2) 10 films were found to greatly increase the in-plane electrical conductivity relative to the W Se2 films, but reduce the in-plane lattice thermal conductivity assuming the Wiedemann-Franz law. © 2007 American Institute of Physics.