Cation‐Deficiency‐Dependent CO<sub>2</sub> Electroreduction over Copper‐Based Ruddlesden–Popper Perovskite Oxides
Jiawei Zhu, Yanying Wang, Aomiao Zhi, Zitao Chen, Lei Shi, Zhenbao Zhang, Yu Zhang, Yu Zhang, Yinlong Zhu, Yinlong Zhu, Xiaoyu Qiu, Xuezeng Tian, Xuedong Bai, Ying Zhang, Ying Zhang, Yongfa Zhu, Yongfa Zhu
Abstract
Abstract We report an effective strategy to enhance CO 2 electroreduction (CER) properties of Cu‐based Ruddlesden–Popper (RP) perovskite oxides by engineering their A‐site cation deficiencies. With La 2− x CuO 4‐δ (L 2− x C, x =0, 0.1, 0.2, and 0.3) as proof‐of‐concept catalysts, we demonstrate that their CER activity and selectivity (to C 2+ or CH 4 ) show either a volcano‐type or an inverted volcano‐type dependence on the x values, with the extreme point at x =0.1. Among them, at −1.4 V, the L 1.9 C delivers the optimal activity (51.3 mA cm −2 ) and selectivity (41.5 %) for C 2+ , comparable to or better than those of most reported Cu‐based oxides, while the L 1.7 C exhibits the best activity (25.1 mA cm −2 ) and selectivity (22.1 %) for CH 4 . Such optimized CER properties could be ascribed to the favorable merits brought by the cation‐deficiency‐induced oxygen vacancies and/or CuO/RP hybrids, including the facilitated adsorption/activation of key reaction species and thus the manipulated reaction pathways.