用于交换膜燃料电池的高效NH3耐受基氧化催化剂
Ye-Hua Wang1, Fei-Yue Gao1, Xiao-Long Zhang1
1Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Journal of the American Chemical Society
|August 1, 2023
概括
这项研究引入了一种新的-合金催化剂 (Cr-MoNi4),该催化剂对燃料电池中的氨中毒具有很高的抵抗力. 这一进步使得使用较低纯度的能燃料电池能够高效地运行,提高性能和耐用性.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 燃料电池可以有效地将转化为电力,但需要超纯.
- 氨 (NH3) 和其他杂质会对碳 (Pt/C) 催化剂中的常规产生毒性,从而降低燃料电池的性能.
- 对于实际的燃料电池应用来说,开发抗杂质毒性强的催化剂至关重要.
研究的目的:
- 为燃料电池开发一种具有增强氨阻力的新型催化剂.
- 在性介质中研究-合金 (Cr-MoNi4) 的催化活性和耐久性.
- 阐明新催化剂耐氨性背后的机制.
主要方法:
- 用添加合金 (Cr-MoNi4) 催化剂的合成和表征.
- 在性氧化反应中对催化剂活性和耐久性的电化学测试.
- 在氨污染的条件下对燃料电池性能进行评估.
- 密度功能理论 (DFT) 的计算,以了解氨吸附机制.
主要成果:
- 这种Cr-MoNi4催化剂对性氧化具有很高的活性.
- 催化剂在2ppm氨气的情况下维持了10,000个周期的活性.
- 使用Cr-MoNi4的燃料电池在10ppm氨气下保持了95%的峰值功率密度,而Pt/C则保持了61%.
- 理论研究表明,兴奋剂通过改变电子性质来减弱氨吸附.
结论:
- 与传统的Pt/C催化剂相比,添加合金 (Cr-MoNi4) 具有更高的氨电阻.
- 在氨的存在下增强的耐用性和性能使得Cr-MoNi4成为实际燃料电池的有希望的候选者.
- 的电子调制是抑制氨中毒的关键,为使用不太纯净的源铺平了道路.
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