Verification and implications of the dissolution–electrodeposition process during the electro-reduction of solid silica in molten CaCl2

Abstract

With the verification of the existence of the dissolution-electrodeposition mechanism during the electro-reduction of solid silica in molten CaCl 2 , the present study not only provides direct scientific support for the controllable electrolytic extraction of nanostructured silicon in molten salts but it also opens an avenue to a continuous silicon extraction process via the electro-deposition of dissolved silicates in molten CaCl 2 . In addition, the present study increases the general understanding of the versatile material extraction route via the electro-deoxidization process of solid oxides in molten salts, which also provokes reconsiderations on the electrochemistry of insulating compounds.

Facile synthesis of freestanding Si nanowire arrays by one-step template-free electro-deoxidation of SiO2 in a molten salt

“…12 Recently CaSiO 3 has been illustrated as a solute medium in the reduction process, which shows another mechanism of mobility of the Si source. 19 Because quartz glass is composed of amorphous SiO 2 and has a relaxing bonding structure, when the solid-to-solid electro-deoxidation occurs and silicon nanoparticles are generated, the surface of quartz glass may become loose and porous, which may result in the movable thin-silk-like SiO 2 . To date the mechanism of this process has not been very clear and needs more exploration.…”

Direct Extraction of Titanium Alloys/Composites from Titanium Compounds Ores in Molten CaCl₂

“…It should be noted that the Si content of the nal Fe/TiC product is determined to be 0.91 mass%, which implies that the trace amount of CaSiO 3 may loss through the dissolution in molten CaCl 2 . Actually, the dissolution of CaSiO 3 in molten CaCl 2 has been con rmed in the previous work and the solubility is determined to be 1.56 mass% at 850 C. 57,58) However, no obvious results show that the formation of CaSiO 3 can affect the production of Ti-Si alloys/composites from titanium/silicon compounds, as shown in Figs. 3-5, these observations are consistent with the previous work.…”

Preparation of porous lead from shape-controlled PbO bulk by in situ electrochemical reduction in ChCl–EG deep eutectic solvent

“…By comparison, it is found that the bulk porosity increases significantly after electrolysis, such as the porosity of the circular pellet is increased from 31.42 to 54.87%. According to literature report [36], the molar volume can well reflect the space size which is occupied by substances with the same molar weight. The calculated results demonstrate that the molar volume of PbO and Pb are 27.9 and 18.18 cm 3 mol −1 , respectively.…”

“…For the high-temperature molten salts [36][37][38][39], the anomalous shrinkage of products is extremely common in the direct electroreduction process of solid oxides. However, because the operating temperature in our study, just about 353 K, is far away from the melting point of metallic lead (600 K), thus the geometry of cathodic bulk can be maintained constant perfectly.…”