改善过渡金属硫化物导电性和循环稳定性是提升超级电容器性能的关键。以二氰二胺和升华硫分别为碳源和硫源,将Ni-MOF前驱体进行碳化和硫化后构筑了二硫化镍纳米颗粒与碳纳米管的复合材料(NiS2@CNTs)。分析表明,碳化样品与升华硫的比例为1∶6时,制得的NiS2@CNTs复合材料具有较大的比表面积,且其中的NiS2纳米颗粒和碳纳米管呈现高分散性,可为电化学储能过程提供丰富的反应活性位点、快速的离子扩散和较强的电子传输效率。电化学性能测试表明,NiS2@CNTs电极在0.5A/g时的比电容可达568.0F/g。以NiS2@CNTs和活性炭(AC)分别为正负极组装NiS2@CNTs//AC器件,其最大输出能量密度和功率密度达15.6和3207.0W/kg,经过5000次充放电循环后的电容保持率和库伦效率分别为98.1%和99.7%,表明该电极材料有望实现长期循环利用且具有良好的实际应用前景。

It is crucial to enhance the electrical conductivity and cycling stability of transition metal sulfides for high performance of supercapacitors. Herein, Nickel disulfide nanoparticles composite carbon nanotubes (NiS2@ CNTs) were fabricated from Ni-MOF precursor after carbonizing and vulcanizing processes. It is found that the NiS2 nanoparticles and CNTs of NiS2@ CNTs composites, which are synthesized under the mass ratio of 1 ∶ 6 between Ni@ CNTs and sublimated sulfur, presenting uniform dispersion and large specific surface area, providing abundant reactive sites, rapid ionic diffusion and strong electron transport efficiency for the electrochemical reaction. The testsshow that the specific capacitance at NiS2@ CNTs reached 568.0 F/ g (0.5 A/ g). By using NiS2@ CNTs and activated carbon (AC) aspositive and negative electrodes, NiS2@ CNTs/ / AC device exhibites the maximum output energy density and power density of 15.6 Wh/ kgand 3 207 W/ kg, and displays as high as 98.1% of capacitance retention and 99.7% of coulombic efficiency after 5 000 cycles, showingthat the electrode is expected to achieve long-term recycling and has a good practical application potential.

0 引言

1 试验

   1.1 原料和试剂

   1.2 材料制备

   1.3 材料表征

   1.4 电极制备及超级电容器组装

   1.5 电化学性能测试

2 结果与讨论

   2.1 结构表征

   2.2 电化学性能

3 结论