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Abstract The electrochemical carbon dioxide reduction reaction (CO2RR) is a promising approach for reducing atmospheric carbon dioxide (CO2) emissions, allowing harmful CO2to be converted into more valuable carbon‐based products. On one hand, single carbon (C1) products have been obtained with high efficiency and show great promise for industrial CO2capture. However, multi‐carbon (C2+) products possess high market value and have demonstrated significant promise as potential products for CO2RR. Due to CO2RR's multiple pathways with similar equilibrium potentials, the extended reaction mechanisms necessary to form C2+products continue to reduce the overall selectivity of CO2‐to‐C2+electroconversion. Meanwhile, CO2RR as a whole faces many challenges relating to system optimization, owing to an intolerance for low surface pH, systemic stability and utilization issues, and a competing side reaction in the form of the H2evolution reaction (HER). Ethylene (C2H4) remains incredibly valuable within the chemical industry; however, the current established method for producing ethylene (steam cracking) contributes to the emission of CO2into the atmosphere. Thus, strategies to significantly increase the efficiency of this technology are essential. This review will discuss the vital factors influencing CO2RR in forming C2H4products and summarize the recent advancements in ethylene electrosynthesis.
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This content will become publicly available on September 2, 2026
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:
- 10640215
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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