A process for the fabrication of high efficiency thermoelectric materials using non-equilibrium synthesis routes is described. In one embodiment a molten alloy comprising a predetermined ratio of elements which will constitute the thermoelectric material is quenched at a cooling rate in excess of, for example, 10.sup.5 or 10.sup.6 K/s using a process such as melt spinning. The rapidly solidified particles are then placed into a mold having the desired size and shape. The particles in the mold are simultaneously compressed and sintered at elevated temperatures for a short duration using, for example, hot pressing or spark plasma sintering. The overall process provides improved microstructural control and greatly expands the accessible phase space, permitting the formation of dense, single-phase structures with nanosized grain boundaries and minimal or no impurity segregation. The process is especially advantageous for the formation of n- and p-type filled skutterudites which may be incorporated in thermoelectric devices.
STATEMENT OF GOVERNMENT RIGHTS
 This invention was made with Government support under contract number DE-AC02-98CH10886, awarded by the U.S. Department of Energy. The Government has certain rights in the invention.