通过局部化状态调节的键裂变将CO2电减转向乙醇
Zhengzheng Liu1, Lu Song1, Ximeng Lv1
1Laboratory of Advanced Materials, Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China.
Journal of the American Chemical Society
|May 7, 2024
概括
铜催化剂可以将二氧化碳 (CO2) 转化为有价值的多碳产品. 这项研究通过功能化铜催化剂来提高乙醇的选择性,达到45%的效率和稳定的转化.
科学领域:
- 电化学
- 催化剂
- 材料科学
背景情况:
- 使用铜基催化剂的电化学二氧化碳 (CO2) 减少是生产附加值多碳 (C2+) 产品的关键策略.
- 由于与CH2CHO*中间体的表面相互作用相关的乙烯的优先形成,对于乙醇等C2+醇来说,实现高选择性是具有挑战性的.
- 乙醇或乙烯的途径是由关键CH2CHO*中间体的Cu-O或OC键的裂变决定的.
研究的目的:
- 通过二氧化碳电还原来提高铜催化剂的选择性.
- 研究表面功能化对催化中间体和反应途径的影响.
- 为工业规模的二氧化碳转化乙醇开发稳定高效的催化剂.
主要方法:
- 采用烯表面功能化方法调整铜催化剂的电子密度,灵感来自硬软酸理论.
- 研究了吸附CH2CHO*中间体中的Cu-O键的削弱和裂变.
- 在工业相关的电流密度下评估膜电极组合电解器的催化剂性能.
主要成果:
- 基功能化铜催化剂显著提高了乙醇的选择性,达到45%的法拉第效率.
- 乙醇生产的最大部分电流密度为406mA·cm−2,超过未经修改和胺功能化的铜催化剂.
- 在电解器中,功能化催化剂在400 mA·cm-2下保持了稳定的CO2转化为乙醇的时间超过300小时.
结论:
- 通过烯表面功能调节的电子移位有效地促进了二氧化碳电减中的乙醇路径.
- 修改后的催化剂通过促进特定的中间键裂变和化来克服C2+酒精选择性的限制.
- 这一战略为高效和稳定的二氧化碳转化为乙醇提供了一个有前途的途径.
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