Synthesis of nanoscale particles of Ta and Nb3Al by homogeneous reduction in liquid ammonia

The analysis of metallothermic reduction as an electronically mediated reac tion predicted that the particle size of solid product could be reduced if the reaction were conducted in a medium that is a mixed conductor (ionic an d electronic). This prediction was confirmed by reacting TaCl5 with sodium, each dissolved in liquid ammonia, to produce tantalum powder having an ave rage particle size over an order of magnitude finer than the micron-sized p owders produced commercially today. Metallothermic reduction in a mixed con ducting medium has been extended to a multicomponent system in order to syn thesize nanosized powder of Nb3Al by co-reduction of NbCl5 and AlCl3 both d issolved in liquid ammonia.