Enhancement of thermoelectric performance of β-Zn 4 Sb 3 through resonant distortion of electronic density of states doped with Gd

The thermoelectric properties of Gd-doped β-Zn 4 Sb 3 are investigated. The results indicate that Gd-doping not only causes a 41 μV K −1 increase in thermopower owing to resonant distortion of DOS but also results in ∼15% reduction in thermal conductivity at a doping content of 0.2%. Consequently, a largest value of ZT = 1.2 is achieved at 655 K.