了解低CO2度电化学转化为CO的局限性
Danielle A Henckel1, Prantik Saha1, Sunil Rajana2
1National Renewable Energy Laboratory, 15013 Denver W Parkway, Golden, Colorado 80401, United States.
概括
电化学二氧化碳减排在低度 (>20%) 和足够的湿度 (50% RH) 中实现了高的二氧化碳选择性. 将二氧化碳降低到10%需要95%的RH和优化电极以达到95%以上的二氧化碳选择性.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 碳捕获和利用是碳的捕获和利用.
背景情况:
- 低温电化学减少二氧化碳 (CO2) 显示高一氧化碳 (CO) 选择性与纯二氧化碳流.
- 对于降低低于30%的二氧化碳度的理解有限,这对于与工业二氧化碳点源集成至关重要.
研究的目的:
- 研究离子体化学和操作条件在低二氧化碳度下的电化学二氧化碳减排过程中对二氧化碳选择性的影响.
- 为了将阴极属性的电化学诊断与CO选择性和催化剂利用相关联.
主要方法:
- 使用先进的电化学诊断来测量阴极催化剂层的离子电阻和电催化剂电容.
- 测量是相对湿度 (RH) 和二氧化碳度的函数.
- 在不同的条件下分析了二氧化碳选择性和催化剂利用率.
主要成果:
- 高的CO/H2选择性 (>95%) 在20%以上的CO2度和至少50%的阴极RH下保持,无论离子体类型如何.
- 在10%的二氧化碳度下,达到95%以上的CO/H2选择性需要95%的RH和电极形态,以促进高催化剂利用.
结论:
- 保持适当的相对湿度和二氧化碳度对于选择性电化学二氧化碳转化为二氧化碳至关重要.
- 电极的设计和形态在达到非常低的二氧化碳度的高选择性方面发挥着重要作用,突出了优化催化剂利用的重要性.
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