Profiles of Carbon Dioxide Decomposition in a Dielectric-Barrier Discharge-Plasma System

Decomposition of CO2 to CO and O2 in Ar stream has been investigated under atmospheric pressure by the use of a dielectric-barrier discharge plasma reactor. CO2 dissociation was found to proceed in accordance with the stoichiometry of 2 CO2 = 2 CO + O2 at considerable rates, which increased with increasing the input voltage, the CO2 concentration in Ar, and the heat of oxide formation of the corresponding metallic component used as the electrode. From kinetic and spectroscopic measurements, the major pathway of CO2 decomposition was speculated to be promoted by a synergetic effect between plasma excitations in the gas phase and catalytic actions of the electrode surface.