A Hybrid Plasma‐Catalysis System for CO2 Hydrogenation over Perovskite‐Type Catalysts: Promoting Effect of A‐Site Substitution. Issue 1 (26th October 2022) - Su, Meng
Abstract : A hybrid dielectric barrier discharge (DBD) plasma‐catalysis system is an effective way to catalyze the conversion of small molecules such as carbon dioxide. Until now, ABO3 perovskite catalyst used for CO2 hydrogenation to light hydrocarbons reaction has been rarely reported. Herein, the lanthanum nickel perovskite‐type catalysts named as La0.8 A'0.2 NiO3± δ (A' represents for Ca, Ce, Pr, Sr) are prepared by a modified nitrate citric acid method, and the influence of A‐site substitution on catalytic performance is investigated. The reactivity results show that the substitution of A‐site can improve CO2 conversion and C2–4 (hydrocarbons containing C2 –C4 ) selectivity in varying degrees. Compared to LaNiO3 catalyst, the La0.8 Ca0.2 NiO3± δ catalyst has CO2 conversion increased from 72.6% to 82.3%, and C2–4 selectivity from 5.8% to 8.5%. The superior performance can be put down to the formation of smaller Ni particle size on La0.8 Ca0.2 NiO3± δ catalyst, which promotes the activation of H2 . Additionally, the sufficient oxygen vacancies on La0.8 Ca0.2 NiO3± δ provide more active sites for CO2 adsorption and then enhance CO2 conversion. The hybrid DBD plasma‐catalysis system is proved effective for CO2 hydrogenation, and the idea of using A‐site substitution would serve as a guide for the modification of perovskite‐type ABO3 catalysts. Abstract : The hybrid dielectric barrier discharge plasma‐catalysis system using LaNiO3 as catalyst is effective to activate CO2 hydrogenation. The substitution of partial La with A' in LaNiO3 promotes CO2 conversion and C2–4 selectivity. The smaller particles size of Ni 0 and more oxygen vacancies in La0.8 Ca0.2 NiO3± δ contribute to its superior performance.