在单位氧降低催化剂中,多离子液体) 离子体有助于防止活性位点聚合
Silvia Favero1, Alain Li1, Mengnan Wang1
1Department of Chemical Engineering, Imperial College London, SW7 2AZ London, U.K.
ACS catalysis
|May 23, 2024
概括
这项研究揭示了离子体对离子交换膜燃料电池 (AEMFC) 的显著而被忽视的影响. 开发新的多离子液体离子体可以改善氧气运输和催化剂层形态,以提高性能.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 能源转换 能源转换
背景情况:
- 阳离子交换膜燃料电池 (AEMFC) 为清洁电力提供无阴极催化.
- 研究主要集中在催化剂和膜上,忽视了离子体的作用.
- 离子体对AEMFC性能和耐久性的影响仍未得到充分研究.
研究的目的:
- 为了研究一种新的基于聚离子液体的离子体对AEMFCs的影响.
- 为了比较这个离子体对氧气运输和还原动力学的影响,与商业离子体 (Nafion,Fumion) 相比.
- 为了将离子体特性与催化剂层形态和燃料电池性能相关联.
主要方法:
- 开发一种以聚离子液体为基础的离子体.
- 使用Nafion和Fumion作为基准,对氧气输送和氧气减少反应 (ORR) 动态进行比较分析.
- 催化剂层形态和铁聚合的表征.
- 催化剂油墨的风湿学分析.
- 使用旋转盘电极 (RDE) 和气体扩散电极 (GDE) 配置的性能测试.
主要成果:
- 离子体的选择显著改变了催化剂层形态和铁聚合.
- 催化剂层质量和铁聚合与催化剂油墨质理相关.
- 与化离子含有多离子液体的聚离子液体与纳米相比,显示出更好的氧气扩散.
- 由于不同的催化剂层形态,在RDE和GDE测试之间观察到显著的性能差异.
结论:
- 离子体在AEMFC的性能和耐用性方面发挥着关键的,往往被低估的作用.
- 聚离子液体) 离子体对增强AEMFC中的氧气运输有希望.
- 突出了RDE测试在预测实际燃料电池性能方面的局限性,强调了GDE评估的必要性.
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