Direct low concentration CO2 electroreduction to multicarbon products via rate-determining step tuning

• Published in: Nature communications Vol. 15; no. 1; pp. 10386 - 14
• Main Authors: Xie, Liangyiqun, Cai, Yanming, Jiang, Yujing, Shen, Meikun, Lam, Jason Chun-Ho, Zhu, Jun-jie, Zhu, Wenlei
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29.11.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/131; 140/133; 140/146; 147/135; 147/143; 639/301/299/886; 639/638/161/886; 704/172/169; 706/4066/4069; Adsorption; Carbon dioxide; Catalysis; Catalysts; Chemistry; Copper; Costs; Dilution; Electrochemistry; Electrolysis; Energy costs; Exhaust emissions; Exhaust gases; Humanities and Social Sciences; Industrial wastes; Intermediates; Microscopy; multidisciplinary; Raw materials; Renewable energy; Science; Science (multidisciplinary)
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-54590-7

Direct converting low concentration CO 2 in industrial exhaust gases to high-value multi-carbon products via renewable-energy-powered electrochemical catalysis provides a sustainable strategy for CO 2 utilization with minimized CO 2 separation and purification capital and energy cost. Nonetheless, the electrocatalytic conversion of dilute CO 2 into value-added chemicals (C 2+ products, e.g., ethylene) is frequently impeded by low CO 2 conversion rate and weak carbon intermediates’ surface adsorption strength. Here, we fabricate a range of Cu catalysts comprising fine-tuned Cu(111)/Cu 2 O(111) interface boundary density crystal structures aimed at optimizing rate-determining step and decreasing the thermodynamic barriers of intermediates’ adsorption. Utilizing interface boundary engineering, we attain a Faradaic efficiency of (51.9 ± 2.8) % and a partial current density of (34.5 ± 6.4) mA·cm −2 for C 2+ products at a dilute CO 2 feed condition (5% CO 2 v/v), comparing to the state-of-art low concentration CO 2 electrolysis. In contrast to the prevailing belief that the CO 2 activation step ( C O 2 + e − + * → C O 2 − * ) governs the reaction rate, we discover that, under dilute CO 2 feed conditions, the rate-determining step shifts to the generation of *COOH ( C O 2 − * + H 2 O → C * O O H + O H − ( a q ) ) at the Cu 0 /Cu 1+ interface boundary, resulting in a better C 2+ production performance. The development of catalysts that operate under low concentration CO 2 resembling industrial waste gases holds promise for CO 2 reduction. Here, the authors report a vacuum calcination approach for regulating the Cu 0 /Cu 1+ density on Cu-based catalysts that can electro-catalyze low-concentration CO 2 .