在水性可充电电池中的反氧活性三角
Kwan Woo Nam1, Heejin Kim2, Yassine Beldjoudi1
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|January 3, 2020
概括
研究人员开发了一种新的有机阴极材料,即基于 (PQ-Δ) 的水性可充电电池 (ZB). 这种材料通过降低界面电阻和改善循环寿命来提高电池性能,为储能提供了有前途的解决方案.
科学领域:
- 材料科学
- 电化学
- 能量储存
背景情况:
- 水性可充电电池 (ZB) 由于其安全性,成本和速率性能,对大规模储能非常有希望.
- 昆化合物是ZB具有吸引力的阴极材料,具有高容量,可持续性和低成本.
- 在循环过程中基阴极的溶解限制了电池的寿命.
研究的目的:
- 为水性可充电电池开发稳定且高性能的正极材料.
- 解决传统阴极的溶解问题.
- 研究新型有机宏循环阴极的性能改善机制.
主要方法:
- 一个基于氧化还原活性三角化 (PQ-Δ) 的宏循环的合成和特征.
- 在水性ZB中测试PQ-Δ作为阴极材料的电化学试验.
- 密度函数理论 (DFT) 计算以阐明界面阻力降低的机制.
主要成果:
- 在 PQ-Δ 阴极中,Zn2+ 离子和H2O 分子被插入,有效降低了接口电阻.
- DFT计算显示,化Zn2+离子的插入降低了溶解能量损失.
- PQ-Δ阴极实现了高可逆容量 (210 mAh g-1) 和卓越的循环稳定性 (在500个循环后保持99.9%).
结论:
- 在PQ-Δ中的刚性三角结构和水合离子插入显著提高了电化学性能.
- 通过二价离子溶解实现的低界面电阻对于二价电池系统至关重要.
- 电子活性有机宏循环是开发ZB先进阴极材料的可行策略.
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