Thermal properties of layered oxychalcogenides BiCuOCh (Ch = S, Se, and Te): A first-principles calculation

The phonon spectra, Debye temperatures, Grüneisen parameters, and the intrinsic lattice thermal conductivities of the layered oxychalcogenides BiCuOCh (Ch = S, Se, Te) have been studied with first-principles calculations. We find that the lattice thermal conductivities of them are anisotropic and quite low. The lowest thermal conductivity is only 0.14 Wm−1K−1 along c-axis for BiCuOTe. The size-dependent thermal conductivity of them is also discussed.