性单原子接口为纯酸燃料电池提供动力
Kai Wei1,2, Mingzi Sun3,4, Xiaoke Xi2
1State Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei 230026, China.
Journal of the American Chemical Society
|April 25, 2025
概括
设计的性单原子催化剂使用纯酸实现了稳定的直接酸燃料电池运行. 这一突破揭示了二氧化碳是一种反应性中间体, 而不是毒素,
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) 为直接酸燃料电池 (DFAFC) 提供高活性.
- 目前的SAC与缩的酸抗争,限制了它们的应用.
- 了解酸中的反应机制至关重要.
研究的目的:
- 调查 DFAFC 的 SAC 中的界面水友性的作用.
- 通过使用高度缩的酸来实现稳定的DFAFC运行.
- 阐明甲酸氧化对SACs的反应机制.
主要方法:
- 将过渡金属单个原子 (Co,Fe,Ni,Ru) 纳入Ir/NC催化剂.
- 用于增强水友性的接口工程.
- 分子动力学模拟和实验验证.
- 在现场光谱和同位素运动分析.
主要成果:
- 在SAC上设计了水友接口.
- 使用纯酸 (>99%) 实现稳定的DFAFC运行.
- 优化的IrCo/NC阳极显示出比纳米粒子催化剂高342倍的质量活性.
- 达到107.7mW cm-2的峰值功率密度.
- 发现CO作为反应性中间体,并确定水参与速度决定的步骤.
结论:
- 对于高性能DFAFC来说,界面的水友性至关重要.
- 水友界面工程使纯酸能够稳定运行.
- 一个新的反应机制涉及CO作为中间体和水参与.
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