Yuan Yu, Cui Panpan, Liu Jie, Ding Wei, Wang Yong, Lv Liping
School of Environmental and Chemical Engineering, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
Key Laboratory of Organic Compound Pollution Control Engineering (MOE), Shanghai University, 99 Shangda Road, Shanghai 200444, China.
Molecules. 2022 Nov 3;27(21):7507. doi: 10.3390/molecules27217507.
Transition metal-based compounds with high theoretical capacitance and low cost represent one class of promising electrode materials for high-performance supercapacitors. However, their low intrinsic electrical conductivity impedes their capacitive effect and further limits their practical application. Rational regulation of their composition and structure is, therefore, necessary to achieve a high electrode performance. Herein, a well-designed carbon-encased mixed-metal selenide rooted with carbon nanotubes (Ni-Co-Se@C-CNT) was derived from nickel-cobalt bimetallic organic frameworks. Due to the unique porous structure, the synergistic effect of bimetal selenides and the in situ growth of carbon nanotubes, the composite exhibits good electrical conductivity, high structural stability and abundant redox active sites. Benefitting from these merits, the Ni-Co-Se@C-CNT exhibited a high specific capacity of 554.1 C g (1108.2 F g) at 1 A g and a superior cycling performance, i.e., 96.4% of the initial capacity was retained after 5000 cycles at 10 A g. Furthermore, a hybrid supercapacitor assembled with Ni-Co-Se@C-CNT cathode and activated carbon (AC) anode shows a superior energy density of 38.2 Wh kg at 1602.1 W kg.
具有高理论电容和低成本的过渡金属基化合物是一类用于高性能超级电容器的有前途的电极材料。然而，它们较低的本征电导率阻碍了其电容效应，并进一步限制了它们的实际应用。因此，合理调控其组成和结构对于实现高电极性能是必要的。在此，一种精心设计的、以碳纳米管为根基的碳包覆混合金属硒化物（Ni-Co-Se@C-CNT）由镍钴双金属有机框架衍生而来。由于独特的多孔结构、双金属硒化物的协同效应以及碳纳米管的原位生长，该复合材料表现出良好的导电性、高结构稳定性和丰富的氧化还原活性位点。受益于这些优点，Ni-Co-Se@C-CNT在1 A g时表现出554.1 C g（1108.2 F g）的高比容量和优异的循环性能，即在10 A g下5000次循环后仍保留96.4%的初始容量。此外，用Ni-Co-Se@C-CNT阴极和活性炭（AC）阳极组装的混合超级电容器在1602.1 W kg时表现出38.2 Wh kg的优异能量密度。
