Hydrodehalogenation of chlorosilanes in the presence of metal silicides: experimental studies of gas and solid phase composition related to thermodynamic calculations

Abstract

Thermodynamic calculations show, in accordance with experimental investigations, that transition metals in an H₂–SiCl₄ atmosphere in the temperature range 600–1200 K will react to form metal silicides. With rising temperature, stoichiometry will change in the direction of silicides with a higher silicon content. The silicides formed in situ act both as a catalyst and a silicon source for the hydrogenation reaction of SiCl₄ to form silanes. On the basis of the formation enthalpy of the silicides, systematization of silicide formation is possible.