在性水氧化过程中揭示了M-N-C单个原子的聚合成高效的MOOH纳米集群
Shanshan Lu1, Zhipu Zhang1, Chuanqi Cheng1
1Department of Chemistry, Institute of Molecular Plus, School of Science, Tianjin University, 300072, Tianjin, China.
Angewandte Chemie (International ed. in English)
|August 27, 2024
概括
金属--碳催化剂 (M-N-C) 在氧化演化反应 (OER) 中聚合. 孤立的原子转化为NiOOH纳米集群,成为增强OER性能的真正活动场所.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 单原子催化剂 (SAC) 的M-N-C类型显示高效率的氧化演化反应 (OER).
- 传统上,M-N-C结构中的孤立金属原子被认为是主要的活性位点.
- 在OER过程中协调的氧化降解可以改变M-N-C结构和反应机制.
研究的目的:
- 研究性OER期间M-N-C材料的结构演变.
- 为了确定对M-N-C催化剂中增强的OER活性负责的实际活跃地点.
- 阐明结构转换的基本机制及其对催化性能的影响.
主要方法:
- 利用多种表征技术分析OER前后的Ni-N-C催化剂.
- 研究了协调物种的溶解产物.
- 检查了碳支上的表面化学变化.
主要成果:
- 在性OER条件下观察到M-N-C材料的显著聚合.
- 证明了协调溶解为酸盐 (NO3-) 和在碳支上形成氧功能组.
- 表明孤立的Ni原子转化为NiOOH纳米集群,这些纳米集群充当了改善OER的实际活性站点.
结论:
- 这项研究揭示了OER期间M-N-C催化剂的溶解-重新沉积机制.
- 孤立的金属原子转化为金属氧化氧化物纳米集群,这是真正的活性点.
- 对Fe-N-C和Co-N-C观察到类似的聚合机制,为M-N-C催化剂演变提供了广泛的见解.
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