Abstract Electrochemical CO2reduction (CO2RR) on copper (Cu) shows promise for higher‐value products beyond CO. However, challenges such as the limited CO2solubility, high overpotentials, and the competing hydrogen evolution reaction (HER) in aqueous electrolytes hinder the practical realization. We propose a functionalized ionic liquid (IL) which generates ion‐CO2adducts and a hydrogen bond donor (HBD) upon CO2absorption to modulate CO2RR on Cu in a non‐aqueous electrolyte. As revealed by transient voltammetry, electrochemical impedance spectroscopy (EIS), and in situ surface‐enhanced Raman spectroscopy (SERS) complemented with image charge augmented quantum‐mechanical/molecular mechanics (IC‐QM/MM) computations, a unique microenvironment is constructed. In this microenvironment, the catalytic activity is primarily governed by the IL and HBD concentrations; former controlling the double layer thickness and the latter modulating the local proton availability. This translates to ample CO2availability, reduced overpotential, and suppressed HER where C4products are obtained. This study deepens the understanding of electrolyte effects in CO2RR and the role of IL ions towards electrocatalytic microenvironment design.
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Recent Advances in Microenvironment Engineering for Selective Electrochemical C–N Coupling
Electrochemical C–N coupling via the coreduction of CO2and nitrogenous species (N2/NOx) presents a sustainable route to synthesize value‐added C–N compounds under mild conditions. However, competing pathways and mismatched intermediate kinetics hinder the selective formation of products like urea, amines, and amides. Recent advances reveal that rational modulation of the electrochemical microenvironment can effectively steer reaction pathways and stabilize coupling‐relevant intermediates. This review systematically summarizes how microenvironment engineering, originally developed for CO2and NOxreduction reactions, can be leveraged to enhance C–N coupling efficiency and selectivity. The key strategies are categorized into 1) catalyst‐centered design (e.g., ligand coordination, defect engineering, and morphology control), 2) ionic and electrolyte modifications (e.g., cation/pH effects), and 3) dynamic approaches such as pulsed electrolysis. These methods shape local fields, surface coverage, and mass transport properties, ultimately directing reactants toward cross‐coupling over competing routes. By drawing parallels with well‐established CO2RR/NOxRR systems and showcasing emerging examples in C–N coupling, the central role of microenvironment control is highlighted. Finally, a perspectives on strategies to further improve activity, selectivity, and atom economy in future C–N coupling systems are offered.
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- Award ID(s):
- 2247194
- PAR ID:
- 10633892
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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