A Study on CO 2 Decomposition to CO and O 2 by the Combination of Catalysis and Dielectric-Barrier Discharges at Low Temperatures and Ambient Pressure

CO 2 decomposition to CO and O 2 was investigated in a dielectric-barrier discharge (DBD) reactor packed with BaTiO 3 balls, glass beads with different sizes, and a mixture of a Ni/SiO 2 catalyst and BaTiO 3 balls at lower temperatures and ambient pressure. The property of packing beads and the reactor configuration affected the reaction significantly. The Ni/SiO 2 catalyst samples were characterized by SEM, XRD, BET, and TEM. The combination of a DBD plasma and a Ni/SiO 2 catalyst can enhance CO 2 decomposition apparently, and a reaction mechanism of the plasma assisted CO 2 dissociation over the catalyst was proposed. In comparison with the result packed with glass balls (3 mm), the combination of BaTiO 3 beads (3 mm) with a stainless steel mesh significantly enhanced the CO 2 conversion and energy efficiency by a factor of 14.8, and that with a Ni/SiO 2 catalyst by a factor of 11.5 in a DBD plasma at a specific input energy (SIE) of 55.2 kJ/L and low temperatures (<115 °C).