在二维导电金属有机框架中,具有层间距的电化学电容性痕迹
Alice Y Su1, Petru Apostol2, Jiande Wang1
1Department of Chemistry, Massachusetts Institute of Technology, 02139, Cambridge, USA.
Angewandte Chemie (International ed. in English)
|February 28, 2024
概括
导电金属有机框架 (MOF) 在电化学电容器中提供快速储能. 调整MOF结构将电荷存储从双层电容转移到伪电容,提高了能量密度.
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:
- 电导金属有机框架 (MOFs) 正在为电化学电容器 (ECs) 探索,因为其高表面积和氧化还原活性.
- 在EC中最大化能量密度涉及双层电容和法拉代过程,这在无机伪电容中很常见.
- 对电荷储存机制和导电MOF中的结构-属性关系的系统研究是有限的.
研究的目的:
- 研究基于三三素的二维导电MOF中的电荷储存机制.
- 了解基功能化如何影响结构参数和电化学性能.
- 建立结构-属性关系,以优化基于MOF的EC中的能量存储.
主要方法:
- 合成了一系列具有不同基组 (R=H,Et,n-Bu,n-Pent) 的 Ni3(HIR3-TAT) 2 MOF.
- 通过R组功能化来表征MOF结构和系统变化的层间距.
- 分析电荷存储机制,区分双层电容和伪电容.
主要成果:
- 基功能调节了层间间距,转移了电荷存储机制.
- 容量从Ni3 ((HIH3-TAT) 2增加到Ni3 ((HIBu3-TAT) 2随着机制转向伪容量.
- 部分脱皮Ni3 ((HIBu3-TAT) 2提高了氧化还原活性部位的可访问性,增加了法拉代的贡献.
结论:
- 调整MOF结构,特别是通过功能化进行层间间距,控制充电存储机制.
- 这一策略增强了摩尔特异性电容,可以用于为EC设计先进的电极材料.
- 了解和控制导电MOF中的电荷储存机制是未来储能应用的关键.
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