Mechanism of plasma chemistry in CO₂ hydrogenation using a dielectric barrier discharge reactor

Plasma-induced CO2 hydrogenation process has received much attention, while the related plasma chemistry has not been profoundly explored. Herein, electron-induced and thermochemical effects on CO2 hydrogenation in a dielectric barrier discharge reactor were investigated. The temperatures for the discharge pattern transition for CO2/H2, CO2/H2/N2, CO2/H2/Ar, and CO2/H2/He mixtures were 623, 623, 600, and 600 K, respectively. CO2 conversion was controlled by electron-induced reactions and was sensitive to discharge pattern and electron density but not electron energy. In contrast, product formation was governed by the thermo-induced chemistry. These results are useful for a better understanding of plasma-induced CO2 hydrogenation.