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.