Thermoelectric Properties of In2O3(ZnO)k (k = 3, 4, 5, 7) Superlattice Ceramics

In 2 O 3 (ZnO) k superlattice ceramics are promising oxide thermoelectric materials, as superlattice interfaces are effective in scattering phonons and filtering low-energy electrons to decrease thermal conductivity and improve the figure of merit ( ZT ) value. In this work, homologous compounds were prepared by solid-state reaction method using ZnO and In 2 O 3 as raw materials. Phase purity and crystal structure were characterized by x-ray diffraction, revealing that In 2 O 3 (ZnO) k crystallizes in an R3 m space group for odd k values and P6 3 /mmc for even k values. The study of thermoelectric (TE) properties showed that as k increased, the thickness of InO(ZnO) + 3 also increased, while the electrical conductivity, thermal conductivity, Seebeck coefficient, power factor and ZT value were all decreased. In 2 O 3 (ZnO) 3 samples obtained a maximum power factor of 651  μ W m −1  K −2 at 973 K, and also achieved a maximum ZT value of 0.24 at 973 K.