1The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081 2National-Provincial Joint Engineering Research Center of High Temperature Materials and Lining Technology, Wuhan University of Science and Technology, Wuhan 430081 3Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education, Wuhan University of Science and Technology, Wuhan 430081
Abstract：We try to use Ho doping combined with band modulation to adjust the thermoelectric properties for BiCuSeO. The results show that Ho doping can increase the carrier concentration and increase the electrical conductivity in the whole temperature range. Although Seebeck coefficient decreases due to the increase of carrier concentration, it still keeps relatively high values, especially in the middle and high temperature range. On this basis, the band-modulation sample can maintain relatively higher carrier concentration while maintaining relatively higher mobility, and further improve the electrical transporting performance. In addition, due to the introduction of a large number of interfaces in the band-modulation samples, the phonon scattering is enhanced effectively and the lattice thermal conductivity is reduced. Finally, the maximal power factor (PF) of 5.18 $\mu$W$\cdot$cm$^{-1}$K$^{-2}$ and the dimensionless thermoelectric figure of merits (ZT) of 0.81 are obtained from the 10% Ho modulation doped sample at 873 K.
2020, Vol. 37 
