双反氧站点使二维结合金属有机框架具有大的伪容量和广泛的潜在窗口
Panpan Zhang1, Mingchao Wang1, Yannan Liu1
1Center for Advancing Electronics Dresden (cfaed) and Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstraße 4, 01062 Dresden, Germany.
Journal of the American Chemical Society
|June 29, 2021
概括
我们开发了新的双氧化位二维合金属有机框架 (c-MOFs),用于先进的超级电容器. 这些材料具有高容量和宽潜在窗口,提高了储能性能.
科学领域:
- 材料科学
- 电化学
- 纳米技术
背景情况:
- 先进的超级电容电极需要在导电性,多孔结构中具有密集的氧化还原点的材料.
- 由于导电性,表面积和对齐的毛孔,二维 (2D) 合金属有机框架 (c-MOF) 是有前途的.
- 现有的二维c-MOF在特定容量和潜在窗口上有局限性,原因是氧化还原位密度低.
研究的目的:
- 为超级电容应用设计和合成具有增强氧化还原活性的新型二维c-MOF.
- 为了改善电化学性能,研究基于铜酸的c-MOF中的双氧化还原位.
- 评估这些新材料的潜在窗口和特定容量.
主要方法:
- 使用铜氨酸和金属氨酸 (M2[CuPc(NH) 8),M=Ni或Cu) 的双氧化位二维c-MOF的合成.
- 电化学特征包括循环电压测量,电静电电荷放电和电化学阻抗光谱.
- 理论计算以验证不同组件作为氧化还原点的作用.
- 准固态对称超级电容器组装用于实际应用测试.
主要成果:
- 合成的M2[CuPc(NH) 8) 材料表现出来自氨酸单体和金属-二 (氨酸) 连接的双氧化还原点.
- 这些材料使 (Na+) 和阴离子 (SO42-) 存储在广泛的电位窗口内 (-0.8到0.8V与Ag/AgCl) 进行连续的法拉代反应.
- Ni2[CuPc(NH) 8在0.5 A g-1时表现出400 F g-1的特异电容,在20 A g-1时表现出优异的速率 (183 F g-1),以及良好的导电能力 (0.8 S m-1).
- 组装的超级电容器实现了高能量密度51.6Wh kg-1和峰值功率密度32.1kW kg-1.
结论:
- 基于M2[CuPc(NH) 8的双氧化场2D c-MOF有效地解决了先前材料的局限性.
- 设计的材料为超级电容器提供了显著改善的特定容量和更大的潜在窗口.
- 这些发现突显了为下一代储能设备量身定制的二维c-MOF的潜力.
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