Dissolution of Calcium Silicates in Molten CaCl2

Electrodeposition of silicon in molten CaCl2 has been drawing increasing attention. Soluble silicate anions the melt can be reduced and tailored into functional materials. To ensure a precise control electrochemical processes, comprehensive knowledge on soluble is indispensable. Here, we clarify formation behavior by dissolving solid CaSiO3 Ca2SiO4 at temperatures from 1047 K to 1233 (774 °C 960 °C). It found that dissolves more faster. The Ca2SiO3Cl2 or Ca3SiO4Cl2 as an intermediate product observed. Metasilicate (SiO32−) orthosilicate (SiO44−) are detected when Ca2SiO4, respectively. Mass transfer these ions plays important role determining overall dissolution rate. polymeric chain-like structure SiO32− reason for slower compared with which SiO44− completely isolated tetrahedral melt. Phase relationships CaCl2–CaSiO3 CaCl2–Ca2SiO4 binary systems CaCl2-rich side clarified. These results should useful manipulating reactions Si (IV) purposes.