花瓣状镍钴层状双金属氢氧化物微球的制备及其超级电容性能

Preparation and Supercapacitors Performances of Nickel-Cobalt Layered Double Hydroxides Microspheres with Flower-Like Patterns

在乙醇-水(V(乙醇)∶V(水)=9∶1)的反应介质中,以SiO2@AlOOH为硬模板,加入镍钴盐前驱体和碱源,水热法制备了花瓣状镍钴层状双金属氢氧化物微球(NiCo-LDHM)。采用扫描电子显电镜、透射电镜和电化学工作站等对此复合材料进行了表征。研究发现,该微球平均粒径约2.5μm,呈多孔结构,由厚度10 nm左右纳米片自组装形成。在1 A/g的电流密度下,该产物电极的比电容量达到1 108.8 F/g,明显优于普通镍钴层状双金属氢氧化物电极(710.5 F/g)的比电容量。当电流密度增加到7 A/g,比电容量为700.8 F/g,恒电流充-放电1 500次后比电容量仍高于94.5%,由此说明了复合材料具有优异的超级电容性能。

Using SiO2@ A1OOH as hard template and adding nickel-cobah precursor and alkali source in ethanol and water （V（CH3CH2OH） ：V（H20） = 9：1）. Nickel-cobah layered double hydroxides microspheres（NiCo-LDHM） with flower-like patterns structure were successfully synthesized by hydrothermal synthesis method. The scanning electron microscope （SEM） ,transmission electron microscope （TEM） and electrochemical workstation were employed for the characterizations of the composite. The results indicated that the microspheres fabricated with nanosheets with the thickness of about 10 nm as in situ formed building units present a porous structure ,and have an average size of about 2.5 ~m. Its maximum specific capacitance was found to be 1 108.8 F/g at current density of 1 A/g,which is obviously higher than that of common nickel-cobalt layered double hydroxides （710.5 A/g）. The specific capacitance can remain at 700.5 F/g when the current density increases to 7 A/g. After galvanostatic charge-discharge 1 500 cycles,the specific capacitance can keep at more than 94.5%,indicating that the composite shows excellent supercapacitor performances.