高耐用性和活性的PtFe纳米催化剂用于电化学氧降解反应
Dong Young Chung1, Samuel Woojoo Jun1, Gabin Yoon1
1Center for Nanoparticle Research, Institute for Basic Science (IBS) , Seoul 151-742, South Korea.
Journal of the American Chemical Society
|December 17, 2015
概括
研究人员开发了一种用于铁 (PtFe) 纳米粒子的新型N-化碳外涂层. 这提高了电催化剂的耐用性和活性,为燃料电池的商业化铺平了道路.
科学领域:
- 材料科学
- 电化学
- 纳米技术
背景情况:
- 对高效电催化剂的日益增长的需求对于燃料电池的商业化至关重要.
- 现有的催化剂在运行条件下通常具有较差的耐用性和活性.
研究的目的:
- 合成具有高度耐用性和活性的金属间有序面中心四角形 (fct) -PtFe纳米粒子 (NP),涂上化碳外.
- 调查N-doped碳外对燃料电池应用中的PtFeNP的保护性和增强活性.
主要方法:
- 通过聚多巴胺涂层的PtFeNP的热合成有序的fct-PtFeNP.
- 在多巴胺涂层中形成薄 (低于1 nm) 的N-化碳外,以防止NP凝聚和溶解.
- 使用现场XANES,EDS和第一原则计算进行表征.
- 在膜电极组件 (MEA) 中测试长期稳定性.
主要成果:
- 通过薄的N-doped碳外来保护高耐久性和活跃的fct-PtFeNP.
- 与商业Pt/C相比,纳米催化剂的质量活性是11.4倍,特异性活性是10.5倍.
- 在MEA中经过100小时的长期稳定性,没有显著的活性损失.
- 证实了fct-PtFe结构在催化剂稳定性中的关键作用.
结论:
- 化碳外策略有效地保护了小型有序的PtFe纳米催化剂.
- 这种方法为开发用于燃料电池商业化的先进电催化剂提供了简单而有效的途径.
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