在膜电极组合CO电解中的电解质效应
Qiucheng Xu1,2, Bjørt Óladóttir Joensen1, Nishithan C Kani1
1Surface Physics and Catalysis (SurfCat) Section, Department of Physics, Technical University of Denmark, Kongens Lyngby, 2800 Kgs., Denmark.
Angewandte Chemie (International ed. in English)
|March 19, 2025
概括
基于膜电极组件 (MEA) 的一氧化碳电解 (COE) 可以产生有价值的C2+产品. 这项研究表明,适度pH的电解质,如碳酸,产生高醇和醇产量,优于高度性条件.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 可持续化学 可持续化学
背景情况:
- 基于膜电极组件 (MEA) 的一氧化碳电解 (COE) 显示出生产C2+产品的前景.
- 在COE的高性能通常在强性条件下 (pH≥14) 实现.
- 极端pH对于最佳COE性能的必要性仍然是一个悬而未决的问题.
研究的目的:
- 研究不同电解质 (碳酸,碳酸,氧化) 对基于MEA的COE性能的影响.
- 了解pH值和阳极氧化对液体产品选择性的影响.
- 通过COE确定生产乙醇和醇的最佳条件.
主要方法:
- 基于MEA的CO电解使用各种电解质 (KHCO3,K2CO3,KOH) 进行.
- 调整了电解质度和pH值,以研究它们对产品选择性的影响.
- 进行了耐用性测试,以评估系统的稳定性.
主要成果:
- 乙醇 (189 ± 5 mA cm−2) 和醇 (89 ± 4 mA cm−2) 的显著部分电流密度是使用 0.5 M K2CO3.3 实现的.
- 在K2CO3电解质中适度的pH条件有利于乙醇和醇的高产量.
- 阳极氧化被确定为对基于MEA的COE性能对C2+生产有害.
结论:
- 基于MEA的最佳COE性能,特别是对于乙醇和醇,可以在中等性条件下实现 (例如0.5M K2CO3).
- 适度的局部性环境和抵抗阳氧化是高选择性的关键因素.
- 尽量减少阳极氧化对于提高基于MEA的COE的耐用性和效率对于有价值的产品合成至关重要.
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