Effects of inorganic salt NaNbO3 composite on the thermoelectric properties of tellurium nanorods thin slice

Abstract

There has recently been increased interest in tellurium nanomaterials (Te NMs)-based thermoelectric (TE) materials owing to their large Seebeck coefficient. Meanwhile, techniques such as doping, alloying, and composite have been intensively investigated to further enhance the TE performance of Te NMs-based energy conversion devices. However, the effects of certain inorganic salts on the TE performance of Te NMs have not been studied thus far. Herein, an inorganic salt NaNbO3 was employed to prepared the Te nanorods (Te-NRs) composite as TE material via a hydrothermal method. Furthermore, the chemical composition, microstructure, thermal stability, and TE performance were systematically investigated for NaNbO3/Te-NRs composites at room temperature. By optimization, the NaNbO3/Te-NRs composite with the mass ratio of 1:1 achieved a simultaneous improvement in Seebeck coefficient and electrical conductivity resulting a large TE power factor (PF) of 43.5 μW m−1 K−2 and a high figure of merit (ZT) of 0.081 which are 8 times higher than the pure Te-NRs. In addition, the introduction of NaNbO3 effectively improves the environmental stability of Te-NRs due to the formation of interfaces between NaNbO3 and Te-NRs. This composite strategy proposed a novel approach to develop a promising TE material.