通过三元PtNi-Au合金ORR催化剂的组合工程平衡活动和稳定性
Xianxian Xie1, Valentín Briega-Martos2, Pere Alemany3
1Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague 8, Czech Republic.
ACS catalysis
|January 9, 2025
概括
研究人员开发了新的--金 (PtNiAu) 合金,以改善质子交换膜燃料电池 (PEMFC). 这些催化剂为氧降解反应 (ORR) 提供了更好的成本,活性和稳定的平衡.
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:
- 质子交换膜燃料电池 (PEMFC) 需要具有成本效益和稳定的氧降解反应 (ORR) 催化剂,以实现更广泛的应用.
- 基催化剂是有效的,但在平衡成本,活动和长期稳定性方面面临挑战.
- 三级合金提供了一个有前途的策略,通过利用多个元素的独特特性来优化催化剂性能.
研究的目的:
- 为了研究ORR催化三元--金 (PtNiAu) 合金的活性-稳定性关系.
- 确定PtNiAu合金的最佳组成,以提高PEMFC应用中的性能和耐用性.
- 了解黄金 (Au) 在提高- (PtNi) ORR催化剂稳定性的作用.
主要方法:
- 使用磁铁子协同喷射制备组合调节的PtNiAu模型层.
- 系统的电化学分析来评估ORR活动和稳定性.
- 补充性特征技术 (如光谱,显微镜) 用于分析催化剂结构和组成.
- 密度函数理论 (DFT) 计算以支持实验发现和阐明反应机制.
主要成果:
- 在PtNiAu合金中的金 (Au) 度从3%增加到15%,导致ORR活性降低,但显著提高了催化剂稳定性.
- 通过抑制 (Pt) 和 (Ni) 溶解来证明这种增强的稳定性.
- 含有15% Au的PtNiAu合金显示出几乎是单金属Pt的三倍活性,并且与PtNi和单金属Pt相比具有更高的溶解稳定性.
- 活动和稳定之间的权衡被观察到,随着Au含量的增加.
结论:
- 三级PtNiAu合金为ORR催化剂提供了一种可行的策略,以实现成本效益,活性和稳定性之间的平衡.
- 添加黄金对于通过减轻组成金属的溶解来提高PtNi合金的耐用性至关重要.
- 这些发现为为PEMFCs设计下一代,具有成本效益和耐用性的催化剂提供了宝贵的见解.
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