Co3O4纳米线阵列@活性炭纤维复合材料的水热合成及电化学应用

以Co(NO₃)₂·6H₂O为钴源, NH₄F和尿素作为添加剂, 通过水热法在粘胶基活性炭纤维(ACF)的表面生长了Co₃O₄纳米线, 制备了Co₃O₄@ACF复合材料并进行了结构形貌表征及电化学性能测试。结果表明: 针状的Co₃O₄纳米线阵列均匀地垂直生长在活性炭纤维表面, 形成了丰富的介孔结构。通过改变Co(NO₃)₂·6H₂O的用量, 可以获得不同负载量的Co₃O₄@ACF复合材料。当Co₃O₄负载量为47wt%时, Co₃O₄@ACF复合材料在1 A/g电流密度下的比电容高达566.9 F/g, 几乎是纯Co₃O₄的2倍; 在15 A/g的电流密度下, 其比电容仍可达到393.3 F/g, 表现了较好的倍率特性; 经过5000次循环充放电后, 其比电容仍可保持84.2%, 展现了优良的循环稳定性。

Co3O4 Nanowire Arrays@Activated Carbon Fiber Composite Materials: Facile Hydrothermal Synthesis and Its Electrochemical Application

Co₃O₄@activated carbon fibers (ACF) composites were prepared through a facile hydrothermal method followed by calcination process, involving the growth of Co₃O₄ nanowires on ACF surface. Co(NO₃)₂·6H₂O was used as Co source, urea and NH₄F as additives. The structures and morphologies of Co₃O₄@ACF composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), N₂ adsorption/desorption measures, and thermogravimetric analysis (TGA). The electrochemical properties of Co₃O₄@ACF composites were investigated by cyclic voltammetry (CV), galvanostatic charge discharge (GCD) and electrochemical impedance spectroscopy (EIS). The results showed that Co₃O₄ nanowire arrays uniformly grew on the surface of ACF along the vertical direction, forming abundant mesoporous structures. Co₃O₄@ACF composites with various Co₃O₄ fractions could be obtained by adding different amount of Co(NO₃)₂·6H₂O. Furthermore, Co₃O₄@ACF composite with 47wt% Co₃O₄ fraction exhibited a high specific capacitance of 566.9 F/g at a current density of 1 A/g, which was almost twice as high as that of pure Co₃O₄. Even at 15 A/g, the composite still delivered a specific capacitance of 393.3 F/g, showing good rate capability. The specific capacitance of the composite could retain 84.2% of initial value after 5000 charging/discharging cycles, which indicates its superior cycling stability.