以1D单元为基础的共价有机框架作为结合剂调节器的方向性黄皮纳米结构
Yiwen Yang1, Fengxue Duan1, Xiaoman Yao1
1Guangdong Provincial Key Laboratory of Carbon Dioxide Resource Utilization, School of Chemistry, South China Normal University, Guangzhou, 510006, P. R. China.
Advanced materials (Deerfield Beach, Fla.)
|May 16, 2025
概括
具有工程纳米结构的新型1D共价有机框架 (1D COF) 提高了硫电池的性能. 与空洞,固体或传统的粘合剂相比,黄COF显著提高了容量和循环稳定性.
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
- 纳米技术纳米技术
背景情况:
- 基于1D单位的共价有机框架 (1D COFs) 显示出由于弱链相互作用的分子组装的前景.
- 在形态工程和储能应用中,特别是硫 (Li-S) 电池中,对1D COF的探索仍然有限.
研究的目的:
- 通过使用溶剂诱导的策略,设计各种1DCOF纳米结构 (蛋黄,空心,固体球体).
- 评估这些1D COF纳米结构作为提高Li-S电池性能的粘合剂调节器.
- 研究纳米形态学和功能组在增强电化学性质中的作用.
主要方法:
- 1D COF纳米结构的溶剂诱导合成:黄皮球 (YS-COF),空心球 (HS-COF) 和固体球 (SS-COF).
- 在Li-S电池电极中加入1D COF作为粘合剂调节器,取代传统的聚乙烯化物 (PVDF).
- 电化学测试 (特定容量,循环稳定性) 和表征.
- 密度函数理论 (DFT) 计算和有限元模拟.
主要成果:
- 与PVDF相比,YS-COF,HS-COF和SS-COF表现出较好的机械性能,体积变化适应性和多硫化物 (LiPSs) 吸附/催化.
- 基于YS-COF的Li-S电池表现出高的初始特定容量,1011 mAh g-1在0.5°C.
- 基于YS-COF的电池在4°C下维持了962 mAh g-1的电量,并循环超过600次.
- DFT和模拟证实了YS-COF纳米形态学和功能组对电化学动学的积极影响.
结论:
- 设计的1D COF纳米结构,特别是黄球,通过作为有效的粘合剂调节器,显著提高了Li-S电池的性能.
- 性能提升归因于增强的机械稳定性,体积变化适应性和优越的LiPS管理.
- 这种形态工程策略为优化先进的能源存储系统中的1D COF提供了一个有希望的途径.
相关概念视频
Metal-Ligand Bonds
19.3K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
19.3K
Valence Bond Theory
8.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
8.9K
Structure of Conjugated Dienes
5.6K
Introduction
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the...
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the...
5.6K
π Molecular Orbitals of 1,3-Butadiene
8.7K
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the...
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the...
8.7K
Stability of Conjugated Dienes
3.4K
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
3.4K
Spin–Spin Coupling: One-Bond Coupling
1.2K
Coupling interactions are strongest between NMR-active nuclei bonded to each other, where spin information can be transmitted directly through the pair of bonding electrons. While nuclei polarize their electrons to the opposite spins, the bonding electron pair has opposite spins. Configurations with antiparallel nuclear spins are expected to be lower in energy. When coupling makes antiparallel states more favorable, J is considered to have a positive value. The one-bond coupling constant, 1J,...
1.2K


