氧化镍/膨胀石墨复合物的合成及其电容性能

采用液相沉淀法制备了膨胀石墨(EG)质量分数为40%的氧化镍/膨胀石墨(NiO/EG)复合物,研究了该复合物电化学性能。结果表明:纳米NiO均匀分散在EG表面;导电性良好的EG显著提高了NiO的电化学性能。在6 mol.L–1 KOH电解液中,NiO/EG复合物电极的氧化和还原峰的电位差降低了0.141 V,100 mA.g–1电流密度下比容量可达到370 F.g–1,远高于纯NiO(约206 F.g–1)和纯EG的比容量(约25 F.g–1)。NiO/EG复合物在充放电500次后,比容量仅衰减了2.5%。

Synthesis and capacitance properties of NiO/EG composite

NiO/EG composite with 40%(mass fraction) EG was synthesized using liquid-phase reaction method and its electrochemical properties were characterized.The results show that NiO nanoparticles can uniformly disperse on the surface of EG and EG plays an important role in increasing the conductivity of NiO.In 6 mol?L–1 KOH electrolyte,the potential difference between the redox peaks of NiO decreases by 0.141 V and the specific capacitance of the composites can reach 370 F? g–1 at current density of 100 mA?g–1,which is much higher than that of pure NiO(ca.206 F? g–1) or EG(ca.25 F?g–1).Furthermore,the reduction in specific capacitance of the NiO/EG composites is only 2.5% after 500 cycles of charge and discharge.