Bhawnani Rajan R, Sartape Rohan, Gande Vamsi V, Barsoum Michael L, Kallon Elias M, Reis Roberto Dos, Dravid Vinayak P, Singh Meenesh R
Department of Chemical Engineering, University of Illinois Chicago, Chicago, IL, 60607, USA.
Department of Materials Science & Engineering, Northwestern University, Evanston, IL, 60208, USA.
Small. 2025 May;21(18):e2408010. doi: 10.1002/smll.202408010. Epub 2024 Dec 8.
Electrochemical CO reduction reaction (CO-RR) in non-aqueous electrolytes offers significant advantages over aqueous systems, as it boosts CO solubility and limits the formation of HCO and CO anions. Metal-organic frameworks (MOFs) in non-aqueous CO-RR makes an attractive system for CO capture and conversion. However, the predominantly organic composition of MOFs limits their electrical conductivity and stability in electrocatalysis, where they suffer from electrolytic decomposition. In this work, electrically conductive and stable Zirconium (Zr)-based porphyrin MOF, specifically PCN-222, metalated with a single-atom Cu has been explored, which serves as an efficient single-atom catalyst (SAC) for CO-RR. PCN- 222(Cu) demonstrates a substantial enhancement in redox activity due to the synergistic effect of the Zr matrix and the single-atom Cu site, facilitating complete reduction of C species under non-aqueous electrolytic conditions. The current densities achieved (≈100 mA cm ) are 4-5 times higher than previously reported values for MOFs, with a faradaic efficiency of up to 40% for acetate production, along with other multivariate C products, which have never been achieved previously in non-aqueous systems. Characterization using X-ray and various spectroscopic techniques, reveals critical insights into the role of the Zr matrix and Cu sites in CO reduction, benchmarking PCN-222(Cu) for MOF-based SAC electrocatalysis.
非水电解质中的电化学一氧化碳还原反应(CO-RR)比水系体系具有显著优势,因为它提高了CO的溶解度,并限制了HCO 和CO 阴离子的形成。非水CO-RR中的金属有机框架(MOF)构成了一个用于CO捕获和转化的有吸引力的体系。然而,MOF主要的有机组成限制了它们在电催化中的导电性和稳定性,在电催化过程中它们会发生电解分解。在这项工作中,研究了一种导电且稳定的基于锆(Zr)的卟啉MOF,特别是PCN-222,其用单原子铜进行了金属化,它可作为CO-RR的高效单原子催化剂(SAC)。由于Zr基体和单原子Cu位点的协同效应,PCN-222(Cu)在氧化还原活性方面有显著增强,有助于在非水电解条件下将C物种完全还原。所实现的电流密度(≈100 mA cm )比先前报道的MOF值高4至5倍,对于乙酸盐生产以及其他多种C产物,法拉第效率高达40%,这在非水体系中是以前从未实现过的。使用X射线和各种光谱技术进行的表征揭示了关于Zr基体和Cu位点在CO还原中的作用的关键见解,为基于MOF的SAC电催化确定了PCN-222(Cu)的基准。