竞争性素吸附控制性氧化活性和基电催化剂的稳定性
Qimei Yang1, Xiaoyun Song1, Hua Fan1
1College of Chemistry and Chemical Engineering, Chongqing University, Chongqing, 400044, China.
Small (Weinheim an der Bergstrasse, Germany)
|October 19, 2025
概括
在催化剂上的阴离子吸附显著影响氧化反应 (HOR) 活性. 化物离子如化物增强HOR性能和稳定性,对于性燃料电池至关重要.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 与贵金属相比,基催化剂在性介质中对氧化反应 (HOR) 的活性有限.
- 阻碍HOR中催化剂性能的机制尚未完全理解,阻碍了高效催化剂的开发.
研究的目的:
- 使用基催化剂研究各种离子 (OH-, Br-, Cl-, SCN-) 对HOR机制的影响.
- 确定离子吸附如何影响HOR动力学,催化剂稳定性和燃料电池整体性能.
主要方法:
- 对离子吸附对Ni基催化剂的影响的实验分析.
- 电化学测量以评估HOR活性和氧化开始潜力.
- 在性离子交换膜燃料电池中测试改性催化剂.
主要成果:
- Br-和Cl-的偏向吸附加速了转移,并增加了HOR限制电流.
- 化物吸附抑制OH-吸附,防止氧化,增强催化剂的稳定性.
- 通过离子吸附,NiMoOx催化剂活性提高了13%;Ni氧化开始潜力延迟了40mV.
- 伪素离子 (SCN-) 由于与Ni的强烈协调,毒害了催化剂.
- Cl-修改的NiMoOx催化剂在燃料电池中达到234.3mW cm-2的峰值功率密度,比未修改的催化剂高1.24倍.
结论:
- 阳离子选择对于优化基催化剂在性HOR中至关重要.
- 化物离子 (Cl-, Br-) 可以增强HOR的催化剂的活性和稳定性.
- 修改后的NiMoOx催化剂显示出高性能性燃料电池的巨大潜力.
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