Enhanced thermoelectric properties of hydrothermally synthesized n-type SeLu-codoped Bi2Te3

摘要

N-type Se&Lu-codoped Bi2Te3 nanopowders were prepared by hydrothermal method and sintered by spark plasma sintering technology to form dense samples.By further doping Se element into Lu-doped Bi2Te3 samples,the thickness of the nanosheets has the tendency to become thinner.The electrical conductivity of Lu0.1Bi1.9Te3−xSex material is reduced with the increasing Se content due to the reduced carrier concentration,while the Seeback coefficient values are enhanced.The lattice thermal conductivity of the Lu0.1Bi1.9Te3−xSex is greatly reduced due to the introduced point defects and atomic mass fluctuation.Finally,the Lu0.1Bi1.9Te2.7Se0.3 sample obtained a maximum ZT value of 0.85 at 420 K.This study provides a low-cost and simple low-temperature method to mass production of Se&Lu-codoped Bi2Te3 with high thermoelectric performance for practical applications.