Table 4.

Equilibrium potentials of possible ECO₂R reactions (RHE = reversible hydrogen electrode).^{[ 140 ]}

Reactions	E° [V vs. RHE]
2H2O → O2 + 4H+ + 4e−	1.23
2H+ + 2e− → H2	0
${\mathrm{CO}}_2+{\mathrm{e}}^{-}\to {\mathrm{CO}}_2^{·-}$	−1.50
CO2 + 2H+ + 2e− → CO + H2O	−0.11
CO2 + 2H+ + 2e− → HCOOH	−0.12
CO2 + 4H+ + 4e− → HCHO + H2O	−0.07
CO2 + 6H+ + 6e− → CH3OH + H2O	0.03
CO2 + 8H+ + 8e− → CH4 + 2H2O	0.17
2CO2 + 8H+ + 8e− → CH3COOH + 2H2O	0.11
2CO2 + 10H+ + 10e− → CH3CHO + 3H2O	0.06
2CO2 + 12H+ + 12e− → C2H4 + 4H2O	0.08
2CO2 + 12H+ + 12e− → C2H5OH + 3H2O	0.09
2CO2 + 14H+ + 14e− → C2H6 + 4H2O	0.14
3CO2 + 18H+ + 18e− → C3H7OH + 5H2O	0.10