燃料电池中的高度稳定和活跃的催化剂通过表面原子排序
Yanling Ma1, Jiaheng Peng1, Jiakang Tian1
1State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P. R. China.
Science advances
|October 18, 2024
概括
研究人员开发了一种新方法来稳定燃料电池的铁合金纳米粒子催化剂. 这种方法提高了耐用性,并保持了高活性,这对于膜电极组件的实际应用至关重要.
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:
- 形状控制的合金纳米粒子催化剂在液体半细胞中显示出氧降解反应 (ORR) 的前景.
- 在将这一成功转化为膜电极组件 (MEA) 催化剂层方面存在挑战,原因是燃料电池条件苛刻,需要耐用性和活性之间的平衡.
研究的目的:
- 制定一种策略,以提高燃料电池MEA中控制形状的铁合金催化剂的稳定性和活性.
- 通过在低温下进行原子排序,使选择性表面转化为有序的金属间结构.
主要方法:
- 采用了一种新的策略来限制表面层内的原子扩散,在热处理过程中促进相位过渡和形状保留.
- 低温热处理有助于通过原子排序选择性地将铁纳米线表面转化为金属间结构.
- 用密度函数计算来研究表面稳定和ORR活动增强的机制.
主要成果:
- 开发的催化剂在MEA中表现出增强的稳定性,铁损失减少了50%.
- 保持了与液体半细胞中观察到的相似的高催化活性.
- 密度函数计算表明,有序的金属间表面增强了对抗腐蚀的形态稳定性,并增强了ORR活动.
结论:
- 通过原子排序进行表面工程是一种有效的策略,用于稳定燃料电池中控制形状的基合金催化剂.
- 这种方法为实际应用提供了潜力,提高了耐用性,并在苛刻的燃料电池环境中保持了活性.
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