原子分散的Fe被限制在MnO纳米集群中 增强性氧降低活性和稳定性
Meng Dan1,2, Xiting Zhang1, Congyi Du1
1School of Chemistry and Chemical Engineering/Institute of Clean Energy Materials/Guangzhou Key Laboratory for Clean Energy and Materials/Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou, 510006, P.R. China.
Angewandte Chemie (International ed. in English)
|May 12, 2025
概括
我们开发了一种新的策略,使用碳支持的铁氧化纳米集群来进行高效的氧降解反应 (ORR). 这种催化剂在性条件和空气电池中表现出极好的活性和稳定性.
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:
- 贵金属催化剂对于氧降解反应 (ORR) 是昂贵的.
- 过渡金属氧化物为ORR催化提供了一个有希望的替代品.
- 开发高效和稳定的电催化剂对于能源应用至关重要.
研究的目的:
- 提出一种金属原子局部化策略,用于在碳支 (MF/CN) 上创建化MnO纳米集群.
- 调查影响ORR活动的电子和结构性质.
- 评估开发的催化剂在性ORR和空气电池中的性能.
主要方法:
- 在碳支 (MF/CN) 上固定的MnO纳米集群中合成原子分散的Fe.
- 实验性表征和理论计算,以了解催化剂的机制.
- 在性介质中对ORR活性和稳定性的电化学测试.
- 在空气电池设置中的性能评估.
主要成果:
- 铁兴奋剂诱导MnO纳米集群中的电荷转移和自旋状态转换,产生活跃的Mn(III) 位点.
- 催化剂表现出强化的内置电场 (BIEF),平衡中间吸附/吸附和增强电子转移.
- 优化的MF0.04/CN显示高ORR活性 (0.79V对RHE) 和稳定性 (>30小时).
- 在Zn-空气电池中,MF0.04/CN实现了138 mW cm-2的功率密度和耐用性 (>666 h).
结论:
- 金属原子定位策略通过调整电子结构和BIEF.有效地提高ORR性能.
- Fe-doped MnO纳米催化剂是一种可行的,具有成本效益的替代优质金属.
- 这项工作为设计用于能源转换设备的高性能金属氧化物异构接口提供了洞察力.
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