在金属有机框架中通过同型连接体替代增强质子导电
SiRim Kim1, Karl W Dawson, Benjamin S Gelfand
1Department of Chemistry, University of Calgary, Calgary, AB, Canada, T2N 1N4.
Journal of the American Chemical Society
|January 5, 2013
概括
研究人员通过交换连接体在金属有机框架 (MOF) 中增强了质子导电性. 这种新材料PCMOF21⁄2显示了质子导电率的1.5倍增加,保持了它的结构.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 导质子金属有机框架 (MOF) 对能源应用至关重要.
- 在保持结构完整的同时提高质子导电性是一个关键的挑战.
- 同型连接体替代提供了针对性材料性能增强的途径.
研究的目的:
- 研究同型连接体替代对MOF中质子导电性的影响.
- 合成和表征一种具有增强质子运输特性的新型MOF材料.
- 为了证明联结体设计在调整MOF性能方面的有效性.
主要方法:
- 在母MOF中,C(3) - 对称的三硫酸连接体与C(3) - 对称的三硫酸连接体的同型替代.
- 基因和改性MOF材料的结构特征.
- 在不同的湿度和温度条件下测量质子导电性.
主要成果:
- 通过连接物交换成功合成PCMOF21⁄2.
- 与母MOF相比,PCMOF21⁄2的质子导电性增加了1.5个数量级.
- 在90%的相对湿度和85°C下,增强的质子导电率达到了2.1 × 10(-2) S cm(-1).
- 在连接体替代后,母MOF结构保持不变.
结论:
- 整体连接体的同态替换是一种有效的策略,可以显著提高MOF中的质子导电性.
- 在保持结构完整的同时,PCMOF21⁄2表现出卓越的质子导电性能.
- 这项工作为设计用于能源技术的先进质子导电MOF提供了新的途径.
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