In such a unipolar or negatively corona discharge, water vapor
and carbon dioxide may form stable negative ions as reducing
agents to form ethanol and methanol. It is our belief that as long
as the total energy of anions obtained from the negative corona
discharge by electron attachment is larger than the Gibbs free
energy differences for the given gaseous reactions, the reduction
process could inevitably be driven forward to products with significant
conversion. It is known [7] that the work needed to remove
electrons from the corona electrode surface is approximately 4–
5 eV for the metals most likely to be used in corona discharge
devices. Since each of reactions (4) and (5) need three moles of
H2O anions or discharged electrons to drive the reactions, 5 eV
energy for each mole of discharged electron or 482.5 kJ/mol is
transferred to system. Once three moles of anions by negative discharge
could form, they may obtain the energy of 1477.5 kJ, which
is beyond the change of the standard Gibbs free energy (1306.1 kJ)
at the standard conditions for reactions (4)–(6), so that those processes
could become fully feasible