Table 1.

Standard electrochemical potentials for CO₂ reduction

Reduction potentials of CO2	E° [V] vs SHE at pH 7
CO2 + e− → CO2 −	−1.9
CO2 + 2H+ + 2e− → HCOOH	−0.61
CO2 + 2H+ + 2e− → CO + H2O	−0.52
2CO2 + 12H+ + 12e− → C2H4 + 4H2O	−0.34
CO2 + 4H+ + 4e− → HCHO + H2O	−0.51
CO2 + 6H+ + 6e− → CH3OH + H2O	−0.38
CO2 + 8H+ + 8e− → CH4 + 2H2O	−0.24
2H+ + 2e– → H2	−0.42