超快速离子运输在2D封闭的mxene中,以提高电化学性能:原子替代 -OH终结
Zhaoxi Liu1, Yapeng Tian1, Jian Yang2
1Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450003, Henan, People's Republic of China.
ACS nano
|November 18, 2024
概括
研究人员使用原子开发了Ti3C2Tx MXene的新表面修饰. 这使得超快的离子传输和高容量可用于先进的能量存储设备.
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
- 纳米技术纳米技术
背景情况:
- 在狭窄的空间中实现超快速离子运输是具有挑战性的.
- 两维 (2D) MXenes提供可调节的结构,但由于负端子而面临运输障碍.
- 表面终端调节是优化2D材料中的离子传输的关键.
研究的目的:
- 开发一种精确修改Ti3C2Tx MXene表面的策略.
- 为了同时增强离子运输和体积电容.
- 探索修改后的MXene在高性能储能方面的潜力.
主要方法:
- 通过超临界CO2处理使用原子对Ti3C2Tx MXene进行表面修饰.
- 改性材料 (SCB-MXene) 的表征,以确认替代和活性位点的保存.
- 作为伪容量材料的SCB-MXene薄膜的电化学测试.
主要成果:
- 成功用原子替代基 (-OH) 末端,形成SCB-MXene.
- 保持氧气 (-O) 活性位点,促进增强的离子运输.
- 在1000 mV s-1下达到742.7 C cm-3的高体积容量.
- 证明了创纪录的能量密度 (66.3 Wh L-1) 和功率密度 (132.5 kW L-1).
结论:
- 提出的表面改造策略有效地克服了基于MXene的离子传输方面的局限性.
- SCB-MXene表现出卓越的电化学性能,使其对储能充满希望.
- 这一进步为下一代大型能源储能和转换设备铺平了道路.
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