激活有缺陷和有氧功能组的石墨,以促进离子储存
Juanxia Ding1,2, Xiaozhong Zhou1, Jian Gao2
1Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education, Key laboratory of Eco-environmental Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, 967 Anning East Road, Lanzhou, 730070, China. zxz20004@163.com.
Nanoscale
|August 14, 2023
概括
活性石墨 (AG) 为离子电池提供了一个有前途的阳极,克服了石墨.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 离子电池 (SIB) 是用于大规模储能的离子电池 (LIB) 的经济高效替代品.
- 在SIB中的石墨阳极由于较弱的结合,因此具有较低的可逆容量.
研究的目的:
- 设计和制造具有增强离子存储性能的活性石墨 (AG).
- 研究通过球磨生产的AG的结构演变和电化学特性.
主要方法:
- 使用一种简单且环保的球磨法制造活性石墨 (AG).
- 通过物理特征来研究结构进化的研究.
- 用于离子存储的AG电极的电化学性能测试.
- 密度函数理论 (DFT) 计算以了解存储机制.
主要成果:
- 在4500个循环后,AG-50电极 (50小时球磨) 在1.0 A g-1下实现了139.1 mA h g-1的稳定可逆容量.
- 观察到每周期0.0034%的显著低容量衰减比.
- 球磨引入了缺陷,扩大了层间距离,增加了表面积,增强了离子储存.
结论:
- 通过球磨加工制造的活性石墨显著提高了离子储存的特异性容量和循环稳定性.
- 增强的性能归因于缺陷部位,这些缺陷部位有助于吸附/脱附.
- 这项工作为开发用于高性能SIB的改性石墨阳极提供了宝贵的参考.
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