介孔碳基钴镍氧化物的电化学电容性能

Electrochemical Capacitive Performance of Mesoporous Carbon Based Co-Ni Oxides

以介孔碳CMK-3为载体,利用CMK-3表面缺陷作形核中心,应用前驱体化学液相共沉淀法制备新型的Co0.25Ni0.75氧化物/CMK-3复合材料.X射线衍射(XRD)分析及扫描电子显微镜(SEM)形貌观察表明该材料主要呈现弱结晶态结构,其中Co-Ni氧化物纳米片交错成空间网络并包覆在介孔碳表面.BET测试表明该材料孔径分布在3～4 nm之间,且高分散、疏松多孔,具有良好的OH-离子传递特性.循环伏安和恒流充放电测试表明,该材料有高的电化学活性,在5 mA/cm2电流密度下,Co0.25Ni0.75氧化物(92%)/C比电容达1781F/g.

By using defects on the surface of CMK-3 served as nucleation center,the Co0.25Ni0.75 oxide/C composite was successfully prepared through a simple chemical co-precipitation method.Characterization was carried out by using X-ray diffraction,BET and scanning electron microscopy.Results showed that a perfect mesoporous network of interconnected nanoflakes was obtained for Co0.25Ni0.75 oxide/C composites.This material was weakly crystallized,interconnected nanoflakes network structure and has a narrow mesoporous distribution at about 3~4 nm.The highly dispersed and loosely packed Co0.25Ni0.75 oxide/C composites possessed good electrochemical accessibility and fast diffusion rate of OH-.Cyclic voltammograms and charge-discharge curves suggested that the as-prepared Co0.25Ni0.75 oxide（92%） /C electrode is highly electrochemical activated and an admirable specific capacitance of as high as 1781 F/g could be obtained at current density of 5 mA/cm2.