Preparation of carbon nanoparticles from electrolysis of molten carbonates and use as anode materials in lithium-ion batteries

CO2 gas decomposition to carbon by electro-reduction in molten salts

“…(10) and (15). 2Ca (l) + CO 2 (g) = C (s) + 2CaO (l) (G 0 1173K = -627.508kJmol -1 [11]) (15) 2Li (l) + CO 2 (g) = CO (g) + Li 2 O (l) (G 0 923K = -273.479kJmol -1 [11]) (16) Ca (l) + CO 2 (g) = CO (g) + CaO (l) (G 0 1173K = -331.212kJmol -1 [11]) (17) LiCl-Li 2 O melt forms CO 3 2-by CO 2 gas bubbling [13][14][15][16], while the formability of CO 3 2-depends on temperature; 15mol%CO 2 dissolves in the melt at 1123 K, but the solubility of CO 2 decreases at the higher temperature corresponding to thermodynamic instability of CaCO 3 [8]. Therefore, the reason why the decrease of CO 2 gas concentration differs significantly would be derived from the difference of electrolysis temperature, i.e., the decrease of CO 2 gas concentration depends on the diffusion rate of oxygen ions especially in ZrO 2 solid electrolyte.…”

“…Then, the anodic reaction Eq. (7) should be modified as, 2O 2-(in molten salt) = 2O 2-(in ZrO 2 ) (13) 2O 2-(in ZrO 2 ) +C (at inner surface of ZrO 2 ) = CO 2 (g) (in ZrO 2 tube) + 4e - (14) The reaction (14) occurs inside the ZrO 2 tube and it is not desired from the viewpoint of complete CO 2 decomposition to carbon and oxygen gas. This technical problem should be clarified in future.…”

“…This experimental paper will report the validity of these reactions except for Eq.(7). Another mechanism is carbonate formation in molten salt [13][14][15][16][17][18][19]. CO 2 gas dissolves as the carbonate ions (Eq.…”

The Charge-Discharge Characteristics of Woody Carbon Modified with Fe<SUB>3</SUB>O<SUB>4</SUB> Nano Phase Using the Hydrothermal Method

“…The C-0.25Fe had a lot of Fe 3 O 4 phases on the surface, so the G-band and D-band were not obvious. Moreover, the index of crystalline of carbon on the surface can be decided by R value (R value is calculated with the G-band and D-band intensity (R ¼ I D =I G ), and a higher R value represents a worse degree of crystallization 19) ). The R values of C, C-0.05Fe and C-0.25Fe were 0.88, 0.82 and 0.67 respectively.…”

Indirect electrochemical reduction of carbon dioxide to carbon nanopowders in molten alkali carbonates: Process variables and product properties

“…In effect, CO 2 was electrochemically reduced to carbon in an indirect manner. Several authors in recent years have confirmed the cathodic deposition of carbon in Li 2 CO 3 -Na 2 CO 3 -K 2 CO 3 (43.5:31.5:25.0, mole ratio) [11][12][13][14][15][16], but to the best of our knowledge only one study [17] reported on carbon deposition in the binary mixture of Li 2 CO 3 -K 2 CO 3 , whilst another [18] used the binary mixture as the electrolyte for the electro-carburisation of mild steel. In both cases, little was attempted to correlate the process variables with the product properties.…”