Enhanced mass transfer in three-dimensional single-atom nickel catalyst with open-pore structure for highly efficient CO2 electrolysis

• Published in: Journal of energy chemistry Vol. 62; pp. 43 - 50
• Main Authors: Zhai, Pengbo, Gu, Xiaokang, Wei, Yi, Zuo, Jinghan, Chen, Qian, Liu, Wei, Jiang, Huaning, Wang, Xingguo, Gong, Yongji
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.11.2021
• Subjects: Catalytic sites; CO2 electrolysis; Open-pore structure; Reactant diffusion; Single-atom catalysts; Single-atom catalysts; Reactant diffusion; CO2 electrolysis; Open-pore structure; Catalytic sites
• ISSN: 2095-4956
• DOI: 10.1016/j.jechem.2021.03.011

Enhanced mass transport within the 3D SANi-G catalyst with open-pore structure leads to boosting selectivity and activity toward CO2 electroreduction. [Display omitted] Design of efficient catalysts for electrochemical reduction of carbon dioxide (CO2) with high selectivity and activity is of great challenge, but significant for managing the global carbon balance. Herein, a series of three-dimensional (3D) single-atom metals anchored on graphene networks (3D SAM-G) with open-pore structure were successfully mass-produced via a facile in-situ calcination technique assisted by NaCl template. As-obtained 3D SANi-G electrode delivers excellent CO Faradaic efficiency (FE) of >96% in the potential range of −0.6 to −0.9 V versus reversible hydrogen electrode (RHE) and a high current density of 66.27 mA cm−2 at −1.0 V versus RHE, outperforming most of the previously reported catalysts tested in H-type cells. Simulations indicate that enhanced mass transport within the 3D open-pore structure effectively increases the catalytically active sites, which in turn leads to simultaneous enhancement on selectivity and activity of 3D SANi-G toward CO2 electroreduction. The cost-effective synthesis approach together with the microstructure design concept inspires new insights for the development of efficient electrocatalysts.