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Updated: Jun 12, 2025

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氧降解反应的双原子催化剂:在反应条件下解原子结构

Courtney Brea^1,2, Guoxiang Hu^3,4

¹Department of Chemistry and Biochemistry, Queens College, City University of New York, New York, New York 11367, United States.

Journal of the American Chemical Society

|May 23, 2025

概括

金属--碳双原子催化剂对燃料电池来说是有前途的. 它们的活性是由运行条件下的动态结构变化所驱动的,FeCo-N-C催化剂的性能优于.

科学领域:

材料科学
电化学
催化剂

背景情况:

质子交换膜燃料电池 (PEMFC) 依赖于高效的氧降解反应 (ORR) 催化剂.
金属--碳 (M-N-C) 双原子催化剂 (DAC) 是的有希望的替代品.
了解DAC在运行条件下的动态结构演变至关重要,但具有挑战性.

研究的目的:

在不同的电化学潜力下研究186个异核FeM-N-CDAC的动态结构演变.
阐明催化机制并预测ORR限制潜力.
为了识别超越基催化剂的DAC.

主要方法:

使用*ab initio*热力学相图来分析186个异核FeM-N-C DAC.
研究应用潜能对活跃地点结构的影响.
研究了电化学修饰金属位点的催化机制.

主要成果:

在较高的应用电位上,OH结合结构变得占主导地位,这表明电化学修饰的活性位控制了活性.
通过相图可以准确预测ORR的限制潜力.
在186种DAC中,有29种表现优于,其中FeCo-N-CDAC表现最高.

结论:

在反应条件下的动态结构变化对于提高DAC电催化性能至关重要.
对于PEMFC,FeCo-N-C DAC是一种高度活跃和有前途的ORR催化剂.
计算预测与实验发现很好地协调,验证了这种方法.

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