Table 1.
Electrochemical potentials of possible CO2 reduction reactions in aqueous solutions for the production of different hydrocarbon fuels
| Possible half‐reactions of electrochemical CO2 reduction | Electrode potentials (V vs SHE) at pH 7 |
|---|---|
| CO2 (g) + e− → *COO− | −1.90 |
| CO2 (g) + 2H+ + 2e− → HCOOH (l) | −0.61 |
| CO2 (g) + H2O (l) + 2e− → HCOO− (aq) + OH− | −0.43 |
| CO2 (g) + 2H+ + 2e− → CO (g) + H2O (l) | −0.53 |
| CO2 (g) + H2O (l) + 2e− → CO (g) + 2OH− | −0.52 |
| CO2 (g) + 4H+ + 2e− → HCHO (l) + H2O (l) | −0.48 |
| CO2 (g) + 3H2O (l) + 4e− → HCHO (l) + 4OH− | −0.89 |
| CO2 (g) + 6H+ (l) + 6e− → CH3OH (l) + H2O (l) | −0.38 |
| CO2 (g) + 5H2O (l) + 6e− → CH3OH (l) + 6OH− | −0.81 |
| CO2 (g) + 8H+ + 8e− → CH4 (g) + 2H2O (l) | −0.24 |
| CO2 (g) + 6H2O (l) + 8e− → CH4 (g) + 8OH− | −0.25 |
| 2CO2 (g) + 12H+ + 12e− → C2H4 (g) + 4H2O (l) | 0.06 |
| 2CO2 (g) + 8H2O (l) + 12e− → C2H4 (g) + 12OH− | −0.34 |
| 2CO2 (g) + 12H+ + 12e− → CH3CH2OH (l) + 3H2O (l) | 0.08 |
| 2CO2 (g) + 9H2O (l) + 12e− → CH3CH2OH (l) + 12OH− (l) | −0.33 |