Thermoelectric Performance of Se/Cd Codoped SnTe via Microwave Solvothermal Method.

Extensive attention has been focused on thermoelectric performance optimization of SnTe because of its potential in waste heat recovery. Here, we fabricate high thermoelectric performance Se/Cd codoped SnTe octahedral particles by microwave-stimulated solvothermal method. The SnTe-based octahedral particles have sizes ranging from several micrometers to hundreds of nanometers, forming dense bulks after spark plasma sintering. Combined with the strong point defect scattering by Se and Cd dopants, a low thermal conductivity of 1.8 W m-1 K-1 at 773 K is obtained in the Se/Cd codoped Sn0.98Cd0.02Te0.9Se0.1 sample. Se and Cd dopants can optimize the band structure of SnTe and boost the power factors, resulting in a promising peak ZT of ∼0.78 at 773 K in the Se/Cd codoped Sn0.98Cd0.02Te0.9Se0.1 sample, which is significantly higher than those of undoped SnTe and Se-doped SnTe samples.