Co-Cu双金属金属有机框架催化剂的性能优于氧气减少的Pt/C基准
Mohamed Fathi Sanad1,2, Alain R Puente Santiago1, Sarah A Tolba3
1Department of Chemistry and Biochemistry, University of Texas at El Paso, 500 W. University Avenue, El Paso, Texas 79968, United States.
Journal of the American Chemical Society
|March 4, 2021
概括
我们开发了一种新型的非贵金属铜双金属有机框架 (MOF) 催化剂. 与基媒介中的催化剂相比,这种MOF表现出更高的氧降解反应 (ORR) 活性和稳定性.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 基于 (Pt) 的纳米材料是氧降解反应 (ORR) 的主要催化剂.
- 高成本和有限的Pt阻碍了燃料电池和金属空气电池的广泛应用.
- 需要为电化学能量转换提供成本高效的替代Pt催化剂.
研究的目的:
- 为ORR设计和合成一种非贵金属金属有机框架 (MOF) 催化剂.
- 评估Co-Cu双金属MOF在性环境中的电催化性能和稳定性.
- 将MOF催化剂的性能与商业Pt/C催化剂和空气电池进行比较.
主要方法:
- 一种Co-Cu双金属MOF的低温水热合成.
- 在0.1M NaOH中对ORR活性和稳定性的MOF催化剂的电化学表征.
- 在空气电池的性能评估.
- 用于电子结构分析的X射线光电子光谱 (XPS) 和状态密度投影仪 (PDOS).
主要成果:
- 与Pt/C相比,Co-Cu双金属MOF表现出更高的ORR电催化活性.
- 实现了1. 06V与RHE的开启电位和0. 95V与RHE的半波电位.
- 在1000次ORR循环后,半波电位仅减少30mV的电化学稳定性.
- 在空气电池的功率密度和可循环性方面表现优于Pt/C.
结论:
- 合理设计的Co-Cu双金属MOF是ORR非常有前途的非珍贵催化剂.
- 在MOF结构中的Co和Cu中心之间独特的电子协同驱动了增强的催化性能.
- 这种MOF为电化学能源设备提供了基于Pt的催化剂的经济有效和高效替代品.
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