在阳离子交换膜中溶解和运输氧化物
Chen Chen1,2, Ying-Lung Steve Tse1, Gerrick E Lindberg3
1Department of Chemistry, James Franck Institute, Institute for Biophysical Dynamics, and Computation Institute, The University of Chicago , Chicago, Illinois 60637, United States.
Journal of the American Chemical Society
|December 31, 2015
概括
离子交换膜 (AEM) 通过车载和格罗特斯机制促进氧化的运输,而离子移动性在较高的温度下增加. 这项研究模拟了AEM中的氧化物行为,以改善膜设计.
科学领域:
- 材料科学
- 电化学
- 计算化学
背景情况:
- 阳离子交换膜 (AEM) 对于电化学应用至关重要,但了解氧化物运输是其设计的关键.
- 需要精确的氧化物溶解和运输模型来优化AEM性能.
研究的目的:
- 开发和应用AEM中的氧化物多尺度反应分子动力学模型.
- 在AEM中研究氧化物溶解结构和运输机制.
主要方法:
- 开发了一种多尺度反应分子动力学模型.
- 修改了适用于离子交换膜材料的模型.
- 在AEM中研究氧化物溶解和运输机制.
主要成果:
- 在AEM内确定了一个连续重叠的氧化物运输区域,由阴离子组的水化组成.
- 发现AEM中的氧化物运输涉及车辆和Grotthuss机制.
- 与质子交换膜 (PEM) 相比,在AEM中观察到更高的自由能障碍和车载运输的更大贡献.
结论:
- 这项研究提供了AEM中氧化物溶解和运输的见解,强调了重叠的水化区域的重要性.
- 在AEM中,氧化的运输是扩散和Grotthuss机制的组合,而车辆运输比PEM更为重要.
- 在AEM中氧化物扩散的更高激活能量表明在高温下离子传输的增强,这对AEM设计至关重要.
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