具有良好的结合结构的α-α合主导的PPy薄膜用于超长周期寿命超级电容器
Jianhua Hong1, Ziyang Dong1, Xuezheng Chen1
1State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti Resources, Hainan University, Haikou 570228, China.
ACS applied materials & interfaces
|February 5, 2024
概括
研究人员开发了一种具有超级电容器增强α-α合的多聚烯 (PPy) 薄膜. 这种纳米结构的PPy膜提高了电容和循环稳定性,克服了常见的电极降解问题.
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
- 聚合物科学 聚合物科学
背景情况:
- 超级电容器的多聚烯 (PPy) 电极面临着由于聚合和交叉连接而导致的结构退化和低电容等挑战.
- 醇单元 (α-α,α-β,β-β) 的合模式显著影响PPy的导电性,合性和稳定性.
研究的目的:
- 为提高超级电容器性能,开发一种具有主导α-α合模式的聚烯 (PPy) 薄膜.
- 研究PPy合结构,纳米结构和电化学性质之间的关系.
主要方法:
- 使用冷界面聚合制造,制造由α-α合主导的PPy薄膜.
- 描述PPy膜的纳米结构和合模式.
- 使用PPy薄膜作为电极对称的水基超级电容器的组装和电化学测试.
主要成果:
- PPy膜呈现出具有增加电化学活性位点的纳米结构.
- 高比例的α-α合导致了增强的π-结合,平面结构,改进的离子传输和均的应力分布.
- 超级电容器在1Ag-1时达到267.1Fg-1的高特异电容,并在6万次循环后保持超过200Fg-1.
结论:
- 冷界面聚合是一种有效的方法,用于创建由α-α合主导的PPy薄膜.
- 优化的PPy结构显著提高了超级电容器的性能,提供高容量和卓越的循环稳定性.
- 这项工作为开发用于储能应用的先进电极材料提供了一个有前途的战略.
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