通过高电流密度的纳米电离体和纳米电离体三明治结构进行选择性质子/质子传输
Saheed Bukola1, Ying Liang2, Carol Korzeniewski2
1Department of Chemistry, Clemson University , Clemson, South Carolina 29634, United States.
Journal of the American Chemical Society
|January 20, 2018
概括
单层石墨烯使多电解质膜的离子电流密度高. 这种基于石墨烯的系统显著增强了质子和子的运输,为高效的燃料技术铺平了道路.
科学领域:
- 材料科学
- 电化学
- 纳米技术
背景情况:
- 多电解质膜 (PEM) 燃料电池对于能源至关重要.
- 通过膜进行有效的离子传输是燃料电池性能的关键.
- 石墨烯的独特特性为新的膜应用提供了潜力.
研究的目的:
- 在PEM式电池中研究通过单层石墨烯的质子和子运输.
- 量化石墨烯对同位素的离子导电性和选择性.
- 探索石墨烯作为选择性离子导电层的潜力.
主要方法:
- 在电池中,单层石墨烯被插入到纳膜之间.
- 使用拉曼光谱来确认石墨烯的质量和完整性.
- 在适度偏差电压下测量离子电流密度和导电量.
主要成果:
- 实现离子电流密度接近1 A cm-2 对于质子和子传输.
- 获得的高面积规范化的离子导电量为:~29 S cm-2 对于质子和~2.1 S cm-2 对于子.
- 显著减弱离子转移,同时允许大量的质子转移.
结论:
- 单层石墨烯在PEM类设备中促进了高效的质子和子运输.
- 石墨烯具有显著的选择性,比质子减弱更重的离子.
- 这些发现表明石墨烯作为电化学应用中的先进离子选择性层的潜力.
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