Abstract
Electrocatalytic reduction of CO2 (CO2RR) under acidic conditions provides a feasible way for converting CO2 to multi-carbon products (C2+) with high feedstock conversion and high energetic efficiency (EE). In this work, poly(ionic liquid) (PIL)-Cu hybrids were employed as excellent acidic CO2RR electrocatalysts. A high faradaic efficiency towards C2+ products (FEC2+) of more than 61.0 % was achieved within a wide pH range from 2 to 14 at –700 mA cm–2. The optimum FEC2+ of 83.1 % was obtained at –700 mA cm–2 and pH = 2, corresponding to an EEC2+ of 37.6 %. By reducing the inlet CO2 flow rate to 1.59 mL min–1, a very high CO2 single-pass conversion of 98.7 % was achieved at –300 mA cm–2. The confinement of PIL layer caused by the semi-rigid abundant porous structure and dense cationic-anionic network enables the maintenance of a moderate local alkaline microenvironment and enrichment of K+ cations at the active sites. These effects jointly promote the C–C coupling at the Cu-PIL interface under acidic conditions. Remarkably, the CO2RR pathway can be regulated by functionality and morphology of the PIL layer.
Original language | English |
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Article number | 124681 |
Journal | Applied Catalysis B: Environmental |
Volume | 361 |
DOIs | |
Publication status | Published - Feb 2025 |
Keywords
- Acidic electrolyte solution
- CO electroreduction
- C–C coupling
- Electrochemistry
- Ploy(ionic liquids)-metal hybrids