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Rechargeable Li-CO2batteries have emerged as promising candidates for next generation batteries due to their low cost, high theoretical capacity, and ability to capture the greenhouse gas CO2. However, these batteries still face challenges such as slow reaction kinetic and short cycle performance due to the accumulation of discharge products. To address this issue, it is necessary to design and develop high efficiency electrocatalysts that can improve CO2reduction reaction. In this study, we report the use of NiMn2O4electrocatalysts combined with multiwall carbon nanotubes as a cathode material in the Li-CO2batteries. This combination proved effective in decomposing discharge products and enhancing cycle performance. The battery shows stable discharge–charge cycles for at least 30 cycles with a high limited capacity of 1000 mAh g−1at current density of 100 mA g−1. Furthermore, the battery with the NiMn2O4@CNT catalyst exhibits a reversible discharge capacity of 2636 mAh g−1. To gain a better understanding of the reaction mechanism of Li-CO2batteries, spectroscopies and microscopies were employed to identify the chemical composition of the discharge products. This work paves a pathway to increase cycle performance in metal-CO2batteries, which could have significant implications for energy storage and the reduction of greenhouse gas emissions.
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Electrochemical CO 2 Reduction in the Presence of Impurities: Influences and Mitigation Strategies
Abstract The electrochemical conversion of waste CO2into useful fuels and chemical products is a promising approach to reduce CO2emissions; however, several challenges still remain to be addressed. Thus far, most CO2reduction studies use pure CO2as the gas reactant, but CO2emissions typically contain a number of gas impurities, such as nitrogen oxides, oxygen gas, and sulfur oxides. Gas impurities in CO2can pose a significant obstacle for efficient CO2electrolysis because they can influence the reaction and catalyst. This Minireview highlights early examples of CO2reduction studies using mixed‐gas feeds, explores strategies to sustain CO2reduction in the presence of gas impurities, and discusses their implications for future progress in this emerging field.
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- Award ID(s):
- 2028351
- PAR ID:
- 10380592
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 52
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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