Rapid synthesis of high-performance thermoelectric materials directly from natural mineral tetrahedrite

Tetrahedrite-structure compounds, of general composition Cu12-xZnxSb4S13, are an earth-abundant alternative to PbTe for thermoelectric power generation applications in the intermediate high-temperature range (300-400 degrees C). Tetrahedrites can be synthesized in the laboratory using a multi-step process involving long annealing times. However, this compound also exists in natural mineral form, and, in fact, is one of the most abundant copper-bearing minerals in the world. We show here that by simply mixing natural mineral tetrahedrite with pure elements through high-energy ball milling without any further heat treatment, we can successfully obtain material with figure of merit near unity at 723 K.