Effects of Te doping on the transport and thermoelectric properties of Zn4Sb3

► Te was successfully substituted for Sb in Zn4Sb3. ► ZT for doped compounds was greater than that of un-doped Zn4Sb3. ► In particular, ZT of Zn4(Sb0.995Te0.005)3 reached a value of 1.08 at 680 K. ► Our results indicate Te doping is an efficient way in improving TE properties.