离子大气的放松控制了塑化二氧化碳氧化还原聚乙烯融中的电子转移动态
Dongil Lee1, Amanda S Harper, Joseph M DeSimone
1Kenan Laboratories of Chemistry and NSF Science & Technology Center for Environmentally Responsible Solvents and Processes, University of North Carolina, Chapel Hill, NC 27599, USA.
Journal of the American Chemical Society
|January 23, 2003
概括
二氧化碳吸附增强了氧化还原聚乙烯融中的电荷传输. 这项研究表明,二氧化碳压力增加了扩散和电子自我交换率,由反放松和聚乙烯溶剂动力学控制.
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
- 物理化学 物理化学
背景情况:
- 化盐材料对电化学应用具有前景.
- 了解电荷传输机制对于优化材料性能至关重要.
- 混合氧化还原聚乙烯融为能量储存和转换提供了独特的特性.
研究的目的:
- 为了研究二氧化碳 (CO2) 吸附在混合氧化还原聚乙烯融中对电荷传输的影响.
- 确定二氧化碳压力如何影响扩散系数和电子自我交换率.
- 阐明电荷传输参数与材料物理性质之间的关系.
主要方法:
- 电化学测量是在混合氧化还原聚乙烯化物上进行的,该混合氧化还原聚乙烯化物是[Co(phenanthroline) ((3) ](MePEG-SO ((3)) ((2)).
- 在23°C时,二氧化碳压力从0到800psi (54 atm) 变化.
- 测量了物理扩散系数 (D ((PHYS),D ((COUNTERION)) 和电子自我交换速率常数 (k ((EX)).
主要成果:
- 二氧化碳吸附显著加速了盐中的电荷传输.
- 增加的二氧化碳压力导致了更高的D{PHYS},k{EX}和D{COUNTERION}.
- 电子自我交换率与扩散系数线性相关,特别是D ((COUNTERION).
结论:
- 电子自我交换速率常数是由复合体周围的反大气放松控制的.
- 聚乙烯溶剂的波动,受二氧化碳吸附的影响,控制对电离体的放松.
- 这项工作展示了一种新的溶剂动力学机制,用于控制半固体氧化还原融中的电子转移.
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