Thermally stable thermoelectric Zn4Sb3 by zone-melting synthesis

The thermal stability of thermoelectric Zn4Sb3 has been investigated on samples produced by a new zone-melting technique, as well as by the conventional quench method. The multitemperature synchrotron powder diffraction data reveal that while conventionally synthesized, Zn4Sb3 samples have almost 40% degradation in the first heating cycle at 625 K, samples prepared by zone melting only have 3% degradation. Repeated thermal cycling induces additional degradation of the quenched sample of up to 58%, compared to similar to 9% degradation in the zone-melted sample. Thus, zone-melting produces Zn4Sb3 samples that are significantly more thermally stable, which make them promising for commercial implementation. (c) 2008 American Institute of Physics.