电子和几何效应 Endow PtRh 破碎的纳米线具有优越的乙醇氧化催化剂
Renqin Yu1, Ruiwen Shao2, Fanghua Ning1
1Institute for Sustainable Energy, College of Sciences, Shanghai University, Shanghai, 200444, China.
Small (Weinheim an der Bergstrasse, Germany)
|October 10, 2023
概括
-凸的纳米线显著提高了直接乙醇燃料电池中的乙醇氧化反应 (EOR). 这些催化剂表现出增强的活性和耐用性,克服了CO中毒,实现了高效的C1通路催化.
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:
- 在C1路径中完成乙醇氧化反应 (EOR) 对直接乙醇燃料电池至关重要,但仍然具有挑战性.
- 为了达到高效率和耐久性,需要先进的电催化剂材料.
研究的目的:
- 开发用于完全氧化乙醇的高活性和稳定的电催化剂.
- 研究新型催化剂的催化机制和结构属性关系.
主要方法:
- 使用湿化学方法合成- (PtRh) 状纳米线.
- 电化学表征包括活性,耐久性和CO耐受性测试.
- 用光谱和计算分析 (XAS,XPS,DFT) 来阐明催化机制.
主要成果:
- PtRh状纳米线显示出异常的EOR质量活性 (1.63 A mgPt-1) 和特异性活性 (4.07 mA cm-2),显著优于Pt/C.
- 初始活动的高保留率 (69.33%在80,000秒后,73.42%在1500周期后) 表明了出色的耐用性.
- 观察到优异的抗CO中毒能力,归因于Rh诱导的电子和几何效应.
结论:
- PtRh状纳米线是通过C1路径完全氧化乙醇的高效电催化剂.
- 增强的性能与修改的Pt─Pt键长和晶格常数有关,促进了反应动力学.
- 这些发现为开发直接乙醇燃料电池的先进催化剂提供了有希望的途径.
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