轴-N诱导的正方形-金字塔晶体充满原子铁站点,以增强酸性氧的减少
Di Shen1, Fanfei Sun2, Zhijian Liang3
1Heilongjiang University, Key Laboratory of Functional Inorganic Materials Chemistry, Ministry of Education of the People's Republic of China, Xuefu Road 74, 150080, Harbin, CHINA.
Angewandte Chemie (International ed. in English)
|June 12, 2025
概括
引入轴协调可显著提高氧降解反应 (ORR) 在酸性介质中的铁基催化剂的性能,增强质子交换膜燃料电池 (PEMFC) 应用.
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:
- 原子分散的Fe基催化剂是氧降解反应 (ORR) 的潜在替代品.
- 常见的FeN4配置在酸性介质中表现出有限的活性和稳定性,阻碍了质子交换膜燃料电池 (PEMFC) 应用.
- 在酸性环境中,Fe溶解是Fe基催化剂面临的关键挑战.
研究的目的:
- 通过使用轴协调来增强酸性ORR原子分散Fe位点的活性和稳定性.
- 研究轴-N对Fe基催化剂电子结构和ORR性能的影响.
- 探索新的催化剂配置,以提高PEMFC效率.
主要方法:
- 计算建模用于研究电子结构和晶体场.
- 在0.10M HClO4电解质中进行电化学测试.
- 操作技术用于分析ORR期间的催化剂行为.
- 质子交换膜燃料电池 (PEMFC) 的制造和测试.
主要成果:
- 在FeN5,FeN5-Fe3和FeN2C3配置中的轴-N协调创建了一个方形金字塔状的晶体场,减少了旋转极化并改变了Fe电子移位.
- 酸性介质中的ORR活性遵循FeN5 > FeN5+Fe3 > FeN2C3 > FeN4的趋势,与增强的电子移位相关.
- 与Pt/C相比,FeN5配置表现出更好的稳定性和活性,半波潜力的积极转移为30mV.
- 操作研究发现Fe-N键解离和FeN5中的氧气插入,形成FeN3O2和FeN4O1中间体,加速ORR动力学.
结论:
- 轴协调是一种有效的策略,可以增强酸性ORR的Fe基催化剂的活性和稳定性.
- FeN5配置显示出卓越的性能,使其成为PEMFC应用的有希望的候选人.
- 了解电子结构的改变和反应中间体对于设计先进的ORR催化剂至关重要.
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