在碳材料中设计化群岛,用于高效的过氧化电化学合成
Shucheng Chen1, Zhihua Chen1, Samira Siahrostami1
1SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering , Stanford University , Stanford , California 94305 , United States.
Journal of the American Chemical Society
|June 7, 2018
概括
嵌入六角化物 (h-BN) 域的和添加碳对2电子氧降解反应 (ORR) 的催化活性增强. 本研究确定这些BCN材料是电化学过氧化生产的新型催化剂.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- 化碳是电化学反应的有希望的催化剂.
- 与和 (BCN) 配合碳增强氧降解反应 (ORR) 的活性.
- 具体的活跃地点和导致 BCN 重要活动的因素需要进一步调查.
研究的目的:
- 合成并系统地研究嵌入六角化物 (h-BN) 领域的 BCN 材料.
- 调查这些 BCN 材料的电化学性能.
- 阐明h-BN域在ORR催化和过氧化生产中的作用.
主要方法:
- 简单且可控的 BCN 材料合成.
- 进行X射线光谱,以描述石墨结构中嵌入的h-BN域.
- 对2电子ORR进行电化学性能测试.
- 密度函数理论 (DFT) 计算以建模催化机制.
主要成果:
- 合成的 BCN 材料在石墨碳结构中显示嵌入的 h-BN 域.
- 这些BCN材料在2e-ORR到H2O2方面表现出优异的活性和选择性.
- DFT计算显示了h-BN域与石墨烯之间的独特催化行为.
结论:
- 在碳结构中嵌入的h-BN域被确定为电化学H2O2生产的新系统.
- h-BN域与石墨烯之间的接口在优先驱动 H2O2生成中起着至关重要的作用.
- 这项工作为选择性ORR提供了NCB材料的催化机制的基本见解.
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