High Thermoelectric Performance and Oxidation Resistance of (Na, Ga) Codoped β-Zn4Sb3 Thermoelectric Materials Prepared by the NaCl Flux

beta-Zn4Sb3 is a promising thermoelectric (TE) material, as it contains low-cost and environment-friendly elements. However, its application has long been limited due to the lower figure of merit (ZT), poor mechanical properties, and inferior thermodynamic stability. In this research, we successfully synthesized Na/Ga codoped beta-Zn4Sb3 with high thermoelectric performance and stability. The power factor (PF) value of the Ga-doped sample is significantly improved by optimizing carrier concentration, the maximum value of 2.28 x 10-3 W m-1 K-2 is obtained at 690 K, and the maximum ZT reaches 1.73 at 690 K for the Zn4.1Sb3(NaCl)7Ga0.12 sample. Moreover, the TG-DSC and oxidation resistance tests show that Na and Ga codoped beta-Zn4Sb3 possess good stability. This work provides an attractive method for improving the thermoelectric properties and stability of beta-Zn4Sb3 through diatomic doping.

Automated summary

In this research, Na/Ga codoped beta-Zn4Sb3 with high thermoelectric performance and stability was successfully synthesized. By optimizing the carrier concentration, the power factor of the Ga-doped sample was significantly improved, reaching a maximum value of 2.28 x 10-3 W m-1 K-2 at 690 K. Moreover, the TG-DSC and oxidation resistance tests demonstrated the good stability of the Na/Ga codoped beta-Zn4Sb3 material. This work provides an attractive method for enhancing the thermoelectric properties and stability of beta-Zn4Sb3 through diatomic doping.