The lattice thermal conductivity of layered group 4 disulfides TiS2, ZrS2, and HfS2 has been studied using dispersion-corrected hybrid density functional methods. Results obtained using both relaxation time approximation (RTA) and full solution of linearized Boltzmann transport equation have been compared and rigorously analyzed. The periodic trends of lattice thermal conductivity and its components are investigated in detail. The in-plane RTA lattice thermal conductivities of TiS2, ZrS2, and HfS2 at 300 K are 6.1, 8.5, and 11.7 W m(-1) K-1, respectively. In the cross-plane direction, where the metal sulfide layers are kept together by weak van der Waals interactions, the RTA lattice thermal conductivities of TiS2, ZrS2, and HfS2 at 300 K are 1.4, 1.4, and 2.0 W m(-1 )K(-1), respectively.
- THERMOELECTRIC PROPERTIES