在非贵重电催化剂上减少氧气的活动描述符识别:将表面科学与协调化学联系起来
Nagappan Ramaswamy1, Urszula Tylus, Qingying Jia
1Northeastern University Center for Renewable Energy Technology, Department of Chemistry and Chemical Biology, Northeastern University , 317 Egan Research Center, 360 Huntington Avenue, Boston, Massachusetts 02115, United States.
Journal of the American Chemical Society
|September 17, 2013
概括
研究人员确定了一个关键因素,用于设计更好的低价值电催化剂,用于减少氧的反应. 调整碳支持的调整.
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
- 表面科学是一门学科.
背景情况:
- 开发高效的非贵金属电催化剂对于燃料电池和金属空气电池至关重要.
- 目前用于非贵金属电催化剂 (Fe-N(x) /C) 的合成方法缺乏基本理解.
- 需要对分子层面的理解来指导先进电催化剂的设计.
研究的目的:
- 阐明氧化非珍贵催化剂氧降解的机制.
- 为了确定氧降解反应 (ORR) 电催化剂的活性描述符.
- 建立催化剂特性和ORR性能之间的关系.
主要方法:
- 机械研究氧气减少在 pyrolyzed 非贵重催化剂.
- 表面科学和协调化学原理的应用.
- 催化活性与碳支性能的相关性,使用C1s光发射光谱学.
主要成果:
- 基于路易斯基本性的石墨碳支的活动描述符被确定.
- 在ORR周转数和碳支持易斯基本性之间发现了线性关系.
- 调整碳基底平面的电子捐赠/提取能力会影响金属离子氧化还原潜力和中间结合强度.
结论:
- 碳支的易斯基本性是非珍贵催化剂中ORR活动的关键描述符.
- 优化碳支的电子特性可以提高电催化剂的性能.
- 这项工作为设计用于能源转换设备的高级非贵金属电催化剂提供了基本的理解.
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