介质效应和催化剂设计一样重要,因为铁-氨酸复合体在电催化氧降低过程中具有选择性
Matthew L Rigsby1, Derek J Wasylenko1, Michael L Pegis1,2
1‡Department of Chemistry, University of Washington, Seattle, Washington 98195-1700, United States.
Journal of the American Chemical Society
|March 24, 2015
概括
介质对氧气减少的电催化剂选择性产生重大影响,通常比催化剂设计更大. 具有质子继电器的催化剂在同一介质中对所需的四电子通路具有更好的选择性.
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
背景情况:
- 铁 - 氨酸复合物正在研究氧降解反应 (ORR) 电催化.
- 了解不同介质中的催化剂选择性对于开发高效的能量转换系统至关重要.
研究的目的:
- 为了评估ORR电催化剂的替代铁氨酸复合物.
- 确定同质和异质介质对催化剂选择性的影响.
- 评估质子继电器在增强ORR选择性的作用.
主要方法:
- 铁氨酸复合物的电催化评估.
- 在各种同质和异质介质中比较催化剂性能.
- 对四电子 (到H2O) 与两电子 (到H2O2) 减少途径的选择性分析.
主要成果:
- 对ORR的催化剂选择性高度依赖于周围的介质.
- 介质对选择性的影响可以超过催化剂的化学修饰.
- 具有质子继电器的铁氨酸催化剂在同一个介质内的直接比较中,对四电子通路的选择性得到了改善.
结论:
- 电催化剂的选择性是催化剂及其中层环境之间的复杂相互作用.
- 支持和可溶性催化剂之间的比较需要仔细考虑介质.
- 质子继电器可以增强所需的ORR通路,但它们的有效性取决于上下文.
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