选择性源于Ag催化CO2的电还原
Shenyu Shen1, Wenshan Zhao1, Mei Xiang2
1School of Chemistry, Engineering Research Center of Energy Storage Materials and Devices of Ministry of Education, National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology, Xi'an Jiaotong University, Xi'an, 710049, China.
The journal of physical chemistry letters
|June 18, 2024
概括
银催化剂可以选择性地将二氧化碳转化为C1产品. 应用的电位和pH值决定了是否通过协同的质子-电子转移 (CPET) 或顺序电子-质子转移 (SEPT) 机制产生酸盐或CO.
科学领域:
- 电化学 电化学 电化学
- 表面科学是一门学科.
- 催化剂是一种催化剂.
背景情况:
- 电化学二氧化碳减排 (CO2R) 对于C1产品合成至关重要.
- 在白银上的反应机制 (CPET与SEPT) 的理解是有争议的.
- 在CO2R.中对C1产品具有很高的选择性.
研究的目的:
- 调查Ag催化电化学CO2R的选择性.
- 阐明应用电位和pH对反应机制的影响.
- 根据反应条件确定C1产品分布.
主要方法:
- 基于马库斯电子转移理论的微动力学建模.
- 在Ag上对二氧化碳减排途径的计算研究111).
- 在不同的应用潜力和pH下对选择性的分析.
主要成果:
- 在pH1.94下,甲酸盐在 -0.94V以下 (CPET) 受到青,而CO在 -0.94V以上 (SEPT) 占主导地位.
- 在pH值13.95时,酸盐是通过SEPT机制产生的主要产物.
- 应用的潜力和pH值显著改变产品的选择性和机制.
结论:
- 提供了对Ag催化CO2R.的机制性见解.
- 通过调整电位和pH,证明对C1产品选择性的控制.
- 为设计高效的二氧化碳减排催化剂提供了一个理论框架.
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