在 π-d 结合协调聚合物中释放以质为主导的氧化活性,以实现高容量和稳定的储存
Kang Han1,2,3, Zhenhang Zhong1, Hao Zhang1
1State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, School of Materials Science and Engineering, Wuhan University of Technology, Wuhan, 430070, P.R. China.
Advanced materials (Deerfield Beach, Fla.)
|August 7, 2025
概括
具有优化d轨道配置的工程协调聚合物使高性能离子电池阳极成为可能. 这一突破提高了下一代储能系统的容量和稳定性.
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 (KIB) 由于成本和资源的可用性,是离子电池的有希望的替代品.
- 开发具有足够容量,稳定性和速率能力的高性能阳极对于KIB的发展至关重要.
- 当前的KIB阳极材料在满足这些性能要求方面面临着挑战.
研究的目的:
- 为设计高性能KIB阳极引入电子结构工程策略.
- 为KIB应用研究d-轨道配置在π-d联协调聚合物的作用.
- 建立基于协调聚合物修改的KIB阳极的一般设计原则.
主要方法:
- 合成 π-d 联协调聚合物 (TM-BTA,TM=Ni,Co,Mn) 的方法.
- 使用轨道水平和电荷密度计算的电子结构分析.
- 电化学性能测试,包括容量,稳定性和速率能力.
- 现场光谱学和密度函数理论 (DFT) 计算以阐明反应机制.
主要成果:
- 尼-BTA表现出卓越的性能,提供452 mAh g-1容量,在500个周期内保持99.2%.
- 观察到异常的长期稳定性,在4000个循环后在1000 mA g-1.1下保持292 mAh g-1.
- 电子结构分析显示,Ni2+的d轨道配置优化了π-d结合,增强了K+吸附动力学并稳定了结构.
- 一个以体为中心的三电子还氧化机制,涉及异环,被确定为主要的K+储存过程.
结论:
- 在协调聚合物中优化D轨道配置是开发高性能KIB阳极的有效策略.
- 尼-BTA 具有出色的电化学特性,使其成为先进的 KIB 阳极的可行候选者.
- 该研究提供了对KIB阳极结构性质关系的基本理解,并为未来材料开发提供了一般设计原则.
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