Excellent Supercapacitor Performance of Robust Nickel-Organic Framework Materials Achieved by Tunable Porosity, Inner-Cluster Redox, and in Situ Fabrication with Graphene Oxide
Excellent Supercapacitor Performance of Robust Nickel-Organic Framework Materials Achieved by Tunable Porosity, Inner-Cluster Redox, and in Situ Fabrication with Graphene Oxide
复制标题
通过可调孔隙率、内团簇氧化还原和氧化石墨烯原位制造实现了坚固的镍有机框架材料的优异超级电容器性能
DOI：
10.1021/acs.cgd.8b00881
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发表时间：
2018-10-01
影响因子：
3.8
通讯作者：
Zhai, Quan-Guo
中科院分区：
文献类型：
--
作者：
Hou, Xiang-Yang;Yan, Xiao-Li;Zhai, Quan-Guo
金属有机框架由于其高孔隙率和可调结构，在超级电容器电极材料中具有广阔的应用前景，但其较差的水稳定性和导电性限制了其电容和效率。为了证明如何克服这些缺点，选择了三种具有[(Ni2NiIII)-Ni-II(mu(3)-OH)(COO)(6)]三核构建块的同结构ni -有机框架。利用高连接的结构，没有开放的金属位点，以及有效的簇内氧化还原过程，三种ni -有机框架在KOH电解质中都是稳定的，并表现出高的伪电容器行为，比电容高达394、426和465 F g（-1）。孔隙度的增加有利于金属离子和电子的扩散，从而提高了它们的电化学性能。此外，我们还证明了用氧化石墨烯原位制备金属有机框架可以有效地提高其超级电容器的性能。当氧化石墨烯掺杂量为3%时，三种化合物的赝电容值分别提高到590、576和504 F g（-1）。这些数值超过了目前报道的大多数金属有机框架超级电容器的数值。这些ni - mof优异的超级电容器性能为利用基于[M-3(mu(3)-OH)(COO)(6)]三核构建块的坚固金属有机框架探索潜在电极材料提供了新的途径。
Metal-organic frameworks have shown promising applications as electrode materials for supercapacitors because of the high porosity and tunable structures, but their poor water stability and conductivity limit their capacitance and efficiency. To demonstrate how to overcome these drawbacks, three isostructural Ni-organic frameworks with [(Ni2NiIII)-Ni-II(mu(3)-OH)(COO)(6)] trinuclear building blocks are selected. Taking advantage of high-connected architectures, absence of open metal sites, and effective inner-cluster redox process, three Ni-organic frameworks all are stable in KOH electrolyte and exhibit a pseudo-capacitor behavior with high specific capacitances up to 394, 426, and 465 F g(-1). The increasing porosity facilitates the diffusion of metal ions and electrons and thus increases their electrochemical performance. Furthermore, we demonstrate that the in situ fabrication of metal-organic frameworks with graphene oxide can effectively promote their supercapacitor performance. With a given 3% graphene oxide doping amount, the pseudo-capacitance values of the three compounds are improved to be 590, 576, and 504 F g(-1) respectively. The values surpass those of most of the reported metal-organic framework supercapacitors up to now. The excellent supercapacitor performance of these Ni-MOFs provides a new route to explore potential electrode material by utilizing robust metal-organic frameworks based on [M-3(mu(3)-OH)(COO)(6)] trinuclear building blocks.