TABLE 2.

Electrochemical potentials of H₂O oxidation and CO₂ reduction into various products.

	Reactions	E 0 (V) vs. NHE at pH 7
1	$2H_{2}O+4h^{+}\to O_2+4H^{+}$	1.23
2	$C{O}_2+e^{-}\to C{O}_2^{-}$	−1.9
3	$C{O}_2+2H^{+}+2e^{-}\to CO+H_{2}O$	−0.53
4	$C{O}_2+2H^{+}+2e^{-}\to HCOOH$	−0.61
5	$C{O}_2+4H^{+}+4e^{-}\to HCHO+H_{2}O$	−0.48
6	$C{O}_2+6H^{+}+6e^{-}\to C{H}_{3}OH+H_{2}O$	−0.38
7	$C{O}_2+8H^{+}+8e^{-}\to C{H}_4+2H_{2}O$	−0.24
8	$2H^{+}+2e^{-}\to H_2$	−0.41