Alternative route for the preparation of CoSb3 and Mg2Si derivatives

• Published in: Journal of solid state chemistry 2012-09, Vol.193, p.109-113
• Main Authors: Godlewska, E., Mars, K., Zawadzka, K.
• Format: Article
• Language: English
• Subjects: CoSb3; Derivatives; Homogenizing; Intermetallics; Magnesium; Magnesium compounds; Mg2Si; Preforms; Semiconductors; Silicides; Synthesis
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2012.03.070

An alternative manufacturing route has been developed for cobalt triantimonide and magnesium disilicide derivatives. Elemental powders were mixed in stoichiometric proportions, cold pressed into cylindrical preforms and heated in oxygen-free environment to initiate the exothermic reaction. According to DTA/TG measurements and observations under high-temperature microscope, the onset of reaction occurred at a temperature not exceeding the melting point of the more volatile component, i.e. antimony in the case of CoSb3 and magnesium in the case of Mg2Si. The reaction products were additionally heat treated to secure homogenization. Dense sinters were obtained by hot uniaxial pressing of the obtained powders in moderate temperature-and-pressure conditions. Several advantages were identified in the proposed technology: absence of liquid phases, relatively short time of the synthesis, possibility of in-situ or ex-situ doping and grain size control. (1) Manufacturing flow sheet for CoSb3 (milling included) and Mg2Si (no milling). (2) Micrographs of CoSb3 product. (3) Micrographs of Mg2Si product. [Display omitted] ► The combustion synthesis followed by HP was used for the manufacturing of CoSb3 or Mg2Si. ► The time of reaction is shorter compared with many other synthesis methods. ► The process is scalable and practically wasteless.