Electrochemical Behavior of Silicon (IV) Ion in BaF₂-CaF₂-SiO₂Melts at 1573K

Studies were performed to investigate the cathodic behavior of silicon (IV) ion in a BaF2-CaF2-SiO2 melt at a temperature of 1573 K. The results obtained show that the silicon (IV) ion was reduced through a single-step from Si4+ + 4e = Si, which was an irreversible process with diffusion-controlled mass transfer. The diffusion coefficient (D) for the reduction process of silicon (IV) ion in BaF2-CaF2-SiO2 melt was 9.76×10−5 cm2 s−1, at 1573 K. Furthermore, galvanostatic electrolysis performed on a molybdenum electrode, which further presents the feasibility of electro-depositing silicon in molten BaF2-CaF2-SiO2 system.