Electrochemical Synthesis of Tantalum Silicides from Chloride-Fluoride Melts

Tantalum silicides: Ta3Si (Tm = 2613 К) , Ta2Si (Tm = 2783 К), Ta5Si3 (Tm = 2833 К) and TaSi2 (Tm = 2313 К) belong to refractory compounds. In the series of refractory compounds, silicides are distinguished by a high chemical stability at high temperatures; therefore, they widely used as protective materials in the chemical industry. Thanks to semiconductor properties and thermal stability, tantalum silicides promise much as a substitute for silicon in microcircuits. Based on thermodynamic calculation and voltammetric studies, it has been concluded that the synthesis of tantalum silicides is the most electropositive process in the NaCl-KCl-K2SiF6-K2TaF7 melts. Only the compound Ta2Si as coatings or powders has been obtained by electrosynthesis of the NaCl-KCl-K2SiF6-K2TaF7 melt at 973 K.