在酸盐电还原过程中原子分散催化剂的结构演变和活动描述
Daniel S Braga1, Angus Pedersen2,3, Mohd Riyaz4
1Institute of Chemistry, University of Campinas, Campinas, SP, 13083-862, Brazil.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|August 23, 2025
概括
单原子催化剂 (SAC) 显示出电化学酸盐降解为氨的潜力. 这项研究揭示了NiNC和CoNC催化剂在电催化过程中形成金属集群,增强了它们的活性,并提供了有效生产氨的设计原则.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 单原子催化剂 (SAC) 对电化学酸盐还原反应 (eNO3RR) 和氨生产具有前景.
- 在电催化过程中了解SAC的现场结构和组成演变对于催化剂设计至关重要,但仍然未被探索.
研究的目的:
- 研究金属--碳 (MNC) 单原子催化剂 (SAC) 的现场结构演变和性能,用于电化学缩反应 (eNO3RR).
- 建立结构活动关系并确定高活性eNO3RR催化剂的设计原则.
主要方法:
- 合成和电化学测试了一系列MNC SACs (M=Cr,Fe,Co,Ni,Cu) 的eNO3RR.
- 使用现场同步X射线光 (SXRF) 映射来探测各种阴极电位下的结构演变.
- 使用实验数据和文献值生成结构活动图.
主要成果:
- NiNC显示出最高的氨法拉第效率 (78.0 ± 2.9%) 和生产率,其次是CoNC.
- 在现场SXRF显示出显著的Ni和Co流动性,导致从0.0V与RHE形成金属集群.
- 在OH结合能量和转换频率之间观察到明显的趋势,金属NiNC和CoNC具有更强的OH结合和更高的活性.
结论:
- 这项研究揭示了eNO3RR期间多国企业的现场结构演变,突出显示了金属结合物流动性和集群形成.
- 与SAC相比,NiNC和CoNC在金属阶段的强OH结合解释了它们的较高的催化活性.
- 这项工作提供了识别活性eNO3RR催化剂的描述符,并提供了对其动态结构变化的见解.
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