Collective Synergistic Catalysis of Electrochemical CO<sub>2</sub> Reduction on Nonstoichiometric Double Perovskites
Zhongxu Wang, Yue Wang, Zongzi Jin, Yongcheng Tong, Chen Li, Ranran Peng, Chengwei Wang, Chusheng Chen, Xiaofeng Tong, Zhongliang Zhan
Abstract
Abstract Perovskite oxides show great promise as an alternative catalyst to the conventional nickel cermets for CO 2 reduction reactions (CO 2 RR) in solid oxide electrolysis cells (SOECs) owing to their advantages of redox stability and coking resistance. Nevertheless, practical applications of these oxides are prevented largely by their poor CO 2 RR activities. Herein, a novel donor and acceptor co‐doped nonstoichiometric double perovskite, La 0.3 Sr 1.55 Fe 1.5 Ni 0.1 Mo 0.4 O 6− δ (LSFNM), is developed with in situ exsolved FeNi 3 nanoparticles to efficiently catalyze CO 2 RR in SOECs. Pure CO 2 electrolysis over the impregnated FeNi 3 @LSFNM catalysts is evaluated on two types of SOECs—one with thin (ZrO 2 ) 0.89 (Sc 2 O 3 ) 0.1 (CeO 2 ) 0.01 (SSZ) electrolytes supported on 430L alloys and the other with thin La 0.9 Sr 0.1 Ga 0.8 Mg 0.2 O 3− δ (LSGM) electrolytes supported on impregnated SmBa 0.5 Sr 0.5 Co 2 O 5+ δ (SBSCO)@LSGM anodes, producing unprecedently high current densities of 2.84 A cm −2 for the former and 3.07 A cm −2 for the latter at 1.5 V and 800 °C. Experimental analysis and density‐functional theory (DFT) calculations reveal collective synergistic catalysis of oxygen vacancies (), the doping Ni 2+ ions and FeNi 3 nanoparticles via the cooperative ‐O(CO 2 ), and Ni(II)–C(sp) and Ni(0)–O(CO 2 ) interactions in LSFNM, not only facilitating CO 2 chemisorption on oxygen vacancies but also destabilizing and dissociating surface carbonates in the vicinity of FeNi 3 spontaneously into CO.