PdRhNi电催化剂对乙醇氧化反应的意想不到的负性能
Ahmed ElSheikh1,2, James McGregor1
1Department of Chemical & Biological Engineering, University of Sheffield, Sheffield S1 3JD, UK.
Micromachines
|May 27, 2023
概括
新的三金属催化剂 (PdRhNi/C) 对直接乙醇燃料电池的性能低于预期. 需要进一步的研究来了解这些新型催化剂在乙醇电氧化反应中的低性能.
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
- 催化剂是一种催化剂.
背景情况:
- 直接乙醇燃料电池 (DEFC) 需要负担得起的新型催化剂进行商业化.
- 三金属催化系统在燃料电池中的氧化还原反应方面尚未得到充分研究.
- 关于 (Rh) 在低DEFC潜力下破解乙醇的C-C键的作用有争议.
研究的目的:
- 在DEFC中合成和评估用于乙醇电氧化反应 (EOR) 的三金属PdRhNi/C电催化剂.
- 为了比较PdRhNi/C与单金属Pd/C,Rh/C和Ni/C催化剂的性能.
- 研究影响催化剂性能的结构和电子特性.
主要方法:
- 一步浸合成PdRhNi/C,Pd/C,Rh/C和Ni/C催化剂.
- 使用循环电压测量 (CV) 和时电压测量 (CA) 的电化学评估.
- 通过XRD,TEM,EDX和XPS进行生理化学表征.
主要成果:
- Rh/C 和 Ni/C 催化剂对 EOR 没有活性.
- 合金PdRhNi纳米粒子 (3nm) 已成功合成.
- PdRhNi/C催化剂的性能低于单金属Pd/C,尽管文献表明单个添加剂可以增强活性.
- 在PdRhNi/C.中观察到较低的Pd表面覆盖面和Pd网格上的压力应变.
结论:
- 合成的PdRhNi/C催化剂不符合DEFC的性能预期.
- 性能下降可能与Pd表面覆盖率降低和网格应变有关.
- 需要进一步的研究,以阐明三金属系统低催化活性背后的精确机制.
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