在中性pH下降解QPPO基离子聚合物电解质膜的降解
Zhiming Feng1, Gaurav Gupta2, Mohamed Mamlouk3
1School of Engineering, Newcastle University Merz Court Newcastle upon Tyne NE1 7RU UK z.feng12@newcastle.ac.uk.
RSC advances
|July 7, 2023
概括
阳离子聚合物电解质膜 (AEMs) 在中性水中显著降解,而不是在性条件下. 这项研究揭示了基于QPPO的AEM在中性水中分解,突出了AEM水电解剂的关键耐用性问题.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 聚合物化学 聚合物化学
背景情况:
- 阳离子聚合物电解质膜 (AEMs) 的化学稳定性对于AEM水电解剂 (AEMWE) 的耐用性至关重要.
- 虽然性稳定性得到了充分的研究,但在接近操作条件的中性pH下,AEM降解被忽视了.
- 在中性pH下AEMs的降解机制尚不清楚.
研究的目的:
- 在各种条件下研究基于四分化聚烯氧化物 (QPPO) 的AEM的化学稳定性.
- 阐明基于QPPO的AEM在中性pH下降解机制.
- 评估IEC对AEM降解的影响.
主要方法:
- 以QPPO为基础的AEM暴露于芬顿溶液,H2O2溶液和脱离离子 (DI) 水中.
- 在60°C的DI水中进行长期氧化稳定性测试,持续10个月.
- 质量损失和离子交换能力 (IEC) 降解的分析.
主要成果:
- 基于QPPO的AEM在芬顿溶液中表现出显著的质量损失 (29%),与原始PPO和ClPPO不同.
- 在QPPO中较高的IEC与较大的质量损失相关,表明对降解的敏感性增加.
- 在60°C的中性DI水中长期浸泡导致QPPO膜分解.
结论:
- 基于QPPO的AEM在中性pH条件下表现出不良的化学稳定性,这对AEMWE的耐用性构成了挑战.
- 这种降解很可能是由对化物甲基基的激进攻击引发的,导致链分裂.
- 需要进一步的研究,以开发更稳定的AEM,用于实际的AEMWE应用.
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