在Ce-Ni3S2中的4f-2p-3d轨道合增强了尿素氧化反应
Wei Zheng1, Naiyuan Duan1, Yang Yang1
1Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
Inorganic chemistry
|July 22, 2024
概括
这项研究引入了一种新型的硫化催化剂 (Ce-Ni3S2/NF),可显著增强可再生能源应用的电催化尿素氧化反应 (UOR).
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 电催化尿素氧化反应 (UOR) 为可再生能源系统提供了一种较低的热力学替代氧化演化反应 (OER).
- 缺乏机理性的理解阻碍了UOR催化剂的优化和商业化.
研究的目的:
- 为UOR开发一种高度活性和耐用的电催化剂.
- 为了阐明Ce-doped Ni3S2对UOR的催化机制.
主要方法:
- 在Ni泡上合成Ce-doped Ni3S2 (Ce-Ni3S2/NF).
- 电化学表征 (电表的斜率,电流密度,耐用性).
- 在现场同步子辐射X射线吸收光谱,FTIR和拉曼光谱.
- 密度函数理论 (DFT) 的计算.
主要成果:
- Ce-Ni3S2/NF在20.3mV dec-1的Tafel斜率下表现出优异的UOR活性,在1.39V与RHE的1.39V下达到100mA cm-2.
- 与未使用剂的Ni3S2/NF.相比,增强了耐用性.
- DFT揭示了Ce兴奋剂通过Ce{4f) -O{2p) -Ni{3d) 轨道合调节Ni电子结构,削弱碳酸中介吸附.
结论:
- 化的Ni3S2/NF是一种高度活跃和持久的UOR催化剂.
- 通过现场光谱和DFT了解该机制,为设计先进的UOR催化剂提供了一条道路.
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