增强的碳-碳合在与突如其来的协调数量变化的接口.
Xuan Wang1, Ruihu Lu2, Binbin Pan1
1Institute of Functional Nano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Advanced Negative Carbon Technologies, Soochow University, Suzhou, 215123, China.
ChemSusChem
|March 12, 2024
概括
设计具有不断变化的协调号码的接口可以显著提高铜催化二氧化碳的减少到C2+化学物质,降低对高效和稳定的生产的能源需求.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 铜催化电化学二氧化碳还原反应 (CO2RR) 对生产有价值的多碳 (C2+) 化学物质充满希望.
- 目前,高超潜力限制了CO2RR技术的实际应用.
- 了解反应机制,特别是C-C键形成途径,对于催化剂设计至关重要.
研究的目的:
- 在CO2RR中设计界面,以减少高C2+法拉代效率 (FE) 的应用潜力.
- 调查协调号 (CN) 变化在接口促进C-C合中的作用.
- 为C2+化学生产开发稳定高效的电催化剂.
主要方法:
- 使用Cu2O衍生的Cu (OD-Cu) 和Cu-phthalocyanine衍生的Cu (PD-Cu) 来制造接口,以创建突然的CN变化.
- 操作X射线吸收光谱 (XAS) 来确定不同接口的协调数和偏好的吸附物种.
- 操作拉曼光谱,以确定反应中间体和途径,如*OCCOH形成.
主要成果:
- 设计的接口与突然的CN变化显著减少了CO2RR的过度潜力.
- OD-Cu的CN值为~11,有利于CO*吸附,而PD-Cu的CN值为~4,有利于COH*吸附.
- 催化剂在220 mA cm-2时实现了85±2%的C2 + FE,与裸体OD-Cu相比,在较低电流密度 (60-140 mA cm-2) 中FE的提高是3倍.
- 在220 mA cm-2下45小时稳定运行被证明,产生C2+产品FE的~80%.
结论:
- 具有突发协调数变化的接口有效地降低了Cu催化CO2RR的过量潜力.
- 界面上的特定的CN值决定了关键中间体的吸附,并影响了C-C键形成路径.
- 该战略为开发高效和稳定的电催化剂提供了一个有希望的途径,用于可持续的C2+化学合成.
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