在电化学降低CO的反向区域
1Department of Chemistry and Key Laboratory of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.
Journal of the American Chemical Society
|June 9, 2023
概括
铜表面的电化学二氧化碳减排机制取决于应用的电力. 一个顺序的电子-质子转移机制在工作电位上占主导地位,而一个协调的质子-电子转移机制在高度负电位上占主导地位.
科学领域:
- 电化学
- 表面科学
- 催化剂
背景情况:
- 电化学二氧化碳减排 (eCO2RR) 对能源和环境应用至关重要.
- 缺乏对铜表面eCO2RR的基本机制理解.
研究的目的:
- 阐明在Cu上的eCO2RR中应用电位和CO2激活动力学之间的相互作用.
- 确定二氧化碳激活机制如何随着应用的潜力而变化.
主要方法:
- 计算模型研究二氧化碳激活机制.
- 电子转移和质子转移步骤的分析.
- 对保利排斥效应的研究.
主要成果:
- 二氧化碳激活机制从顺序电子 - 质子转移 (SEPT) 转变为协同的质子 - 电子转移 (CPET),应用电位下降.
- 由于保利排斥,在SEPT的电子转移屏障中观察到一个反转区域.
- 建议设计催化剂以减轻保利排斥效应.
结论:
- 应用潜力决定了eCO2RR在Cu上的占主导地位的CO2激活机制.
- 在低电位下,保利排斥显著影响了电子转移步骤.
- 这些发现为封闭分子的电化学还原提供了一般的见解.
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