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  • Non‐Aqueous Electrochemical CO 2 Reduction to Multivariate C 2 ‐Products Over Single Atom Catalyst at Current Density up to 100 mA cm −2
Title: Non‐Aqueous Electrochemical CO 2 Reduction to Multivariate C 2 ‐Products Over Single Atom Catalyst at Current Density up to 100 mA cm −2
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.  more » « less
Award ID(s):
2326714 2420733
PAR ID:
10568650
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Small
ISSN:
1613-6810
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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