Abstract:Nanosized silicon with several micrometers in length and 200 nm in width was synthesized by molten salt electrolysis method at 700 ℃ under cell voltage of 1.8 V for 5 h applying SiO2 powder as cathode raw material, equimolar CaCl2-NaCl mixed molten salt as electrolyte and graphite rod as anode. Effect of molten salt on cathode raw SiO2 was investigated. After rinsed in molten salt for 2 h at 700 ℃, raw material SiO2 is characterized by XRD and SEM. The results suggest that phase of raw material is unchanged but morphology has been converted from initial spheroidal particles to inter-linked network and porous structure. During electrolysis of SiO2, intermediate CaSiO3 is produced, which is further electrolyzed for final formation of metallic silicon.