Electrochemical conversion of CO₂ into value-added carbon with desirable structures via molten carbonates electrolysis

Abstract

CO2 is indirectly converted into carbon nanotubes, carbon spheres and honeycomb carbon in the molten carbonate electrolyte. This research is helpful to alleviate global climate change and is of great significance to the realization of sustainable development of mankind.

New Route of Acetylene Synthesis via Electrochemical Formation of Metal Carbides from CO2 in Chloride Melts

“…The unique physicochemical properties of the melts make it possible to obtain solid carbon directly from CO 2 gas − according to the following reaction. normalC normalO 2 + 4 e − → normalC + 2 normalO 2 − In the case of melts containing oxide ions, CO 2 can be dissolved in the form of carbonate ions normalC normalO 2 + O 2 − → C O 3 2 − The carbonate ions are reduced to the solid carbon on a cathode as follows. C O 3 2 − + 4 e − → normalC + 3 normalO 2 − Many studies on the carbon electrodeposition from carbonate ions in molten alkali carbonate mixtures − and molten halides containing metallic carbonates − have been reported.…”

CO2 Electroreduction in Organic Aprotic Solvents: A Mini Review

“…Among them, the most studied are ionic liquids [19][20][21][22][23][24][25][26], methanol solutions [27][28][29], and organic aprotic solvents [30][31][32][33][34][35][36][37][38][39][40]. In recent years, there has also been engagement in the CO 2 electrochemical reduction process in molten salts [41][42][43][44][45][46]. e following valuable nanomaterials can be obtained in such an environment: carbon nanofibers [43], carbon nanotubes (CNTs), carbon spheres (CSs), and honeycomb carbon [44].…”

“…In recent years, there has also been engagement in the CO 2 electrochemical reduction process in molten salts [41][42][43][44][45][46]. e following valuable nanomaterials can be obtained in such an environment: carbon nanofibers [43], carbon nanotubes (CNTs), carbon spheres (CSs), and honeycomb carbon [44]. In addition, the simplicity of the design of the diaphragm-free electrolyzer (Figure 4), high conversion speed (i cathode = 100 mA × cm − 2 ), and high Faradaic efficiency (80-90%) of products [42] make this method promising.…”