Nonthermal Plasma‐Assisted CO₂‐H₂O Conversion over NiO and Co₃O₄ Supported on CeO₂

Abstract Transformation of CO 2 into value‐added chemicals remains a key challenge. Herein, nonthermal plasma (NTP)‐activated CO 2 ‐H 2 O conversion over BaTiO 3 ‐mixed NiO/CeO 2 (Ni/Ce + ) and Co 3 O 4 /CeO 2 (Co/Ce + ) catalysts is demonstrated. In a continuous‐flow dielectric barrier discharge reactor and under ambient conditions, optimum Co/Ce + showed formation rates of CO and O 2 of (43.6 ± 3.1) and (20.8 ± 0.7) μmol g −1 h −1 , respectively. CO 2 conversion was found to be dependent on a combination of the basicity of the catalyst surface, CO 2 flow rate, plasma input power, and relative humidity. Subsequently, kinetic analysis suggested that the activation energies over Ni/Ce + , Co/Ce + , and NiCo/Ce + are 35.68, 15.61, and 25.88 kJ mol −1 , respectively. By combining these findings, a plausible reaction mechanism that can facilitate understanding the trend of product formation is also provided.