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The strong binding energy of CO on iron surfaces has rendered Fe electrodes as poor electrochemical CO₂reduction (eCO2R) catalysts, predominantly producing hydrogen. Recent studies on tuning the microenvironment near the catalyst surfaces by tuning the local electric field in nonaqueous environments have been shown to promote eCO2R by facilitating the CO₂activation step. Herein, the use of tetraethylammonium (TEA) cation to tune the electric field on Fe surfaces, such that it leads to the formation of industrially relevant oxalates (C₂products), is reported. At optimal cation concentrations, the developed eCO2R system achieves 25 mA cm⁻²of current density and Faradaic Efficiencies up to 75% toward oxalate. Furthermore, in situ attenuated total reflectance Fourier transform infrared spectroscopy indicates the presence of surface‐adsorbed TEA cations and other species on the Fe surfaces, leading to the well‐known outer‐sphere mechanism of electron transfer during eCO2R. The employment of Fe, along with microenvironment tuning, not only demonstrates high catalytic performance but also provides a safer and more sustainable alternative to toxic catalysts such as Pb that dominate the nonaqueous eCO₂R literature. These findings pave the way for further optimization and scale‐up of the process, offering a viable route for sustainable chemical production and CO₂mitigation. 

Abstract Electrochemical CO₂reduction reaction (CO₂‐RR) in non‐aqueous electrolytes offers significant advantages over aqueous systems, as it boosts CO₂solubility and limits the formation of HCO₃⁻and CO₃²⁻anions. Metal–organic frameworks (MOFs) in non‐aqueous CO₂‐RR makes an attractive system for CO₂capture 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 CO₂‐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 C₂species under non‐aqueous electrolytic conditions. The current densities achieved (≈100 mA cm⁻²) 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 C₂products, 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 CO₂reduction, benchmarking PCN‐222(Cu) for MOF‐based SAC electrocatalysis.