超越小分子离子:在膜尺度上阐明离子分子的性稳定性
Qianjun Ling1, Chenxi Wang1, Tao Wang1
1Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei, 230009, China.
ChemSusChem
|December 16, 2023
概括
这项研究揭示了四级基在性离子交换膜 (AEM) 中比piperidinium更稳定,挑战了以前的假设,并提高了电化学设备的AEM耐用性.
科学领域:
- 电化学 电化学 电化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 性聚电解质电化学装置的商业化受阻于缺乏持久的离子交换膜 (AEM).
- 在膜水平上,各种阴离子部分的性稳定性仍然不太清楚.
研究的目的:
- 为了分子设计和合成一个多芳香的AEM与交替的阴离子部分.
- 为了在膜尺度上的多芳香基架中,在 piperidinium 和四级氨基群之间的稳定性中提供无偏见的比较.
主要方法:
- 一个分子设计的多芳离子交换膜 (AEM) 的合成.
- 现场性浸泡和现场电化学电池操作以评估膜稳定性.
- 核磁共振 (NMR) 光谱法用于量化阴离子组的稳定性.
- 密度函数理论 (DFT) 为了合理化恶化机制.
主要成果:
- 三甲基组在多芳香的支架中,与 piperidinium 组相比,其性稳定性大约是 2 倍.
- 在ex-situ和in-situ条件下观察到这种稳定性差异.
- 密度函数理论的计算提供了对piperidinium部分降解机制的见解.
结论:
- 这项研究挑战了普遍的假设,即基于piperidinium的AEM在本质上比基于四级的AEM更加稳定.
- 四级氨基团,特别是三甲基,在多芳香的AEM中提供优越的性稳定性.
- 这些发现为开发更耐用的AEMs为先进的电化学能量转换设备铺平了道路.
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