多级结构镍钴氧化物复合材料的制备及其电容性能

Fabrication of Ni-Co oxide composites with hierarchically structure and its capacitance properties

为提升Co3O4材料的实际电容性能,设计一种多级结构的双金属镍钴复合材料。采用水热法将碱式碳酸钴纳米片原位生长于碳纤维布上(CC@CCH NS);再利用电沉积法将层状结构的镍钴双氢氧化物生长在碱式碳酸钴纳米片上(CC@CCH NS@NiCo LDH),退火处理后得到多级结构CC@Co3O4@NiCo2O4复合材料。测试结果表明:CC@Co3O4@NiCo2O4复合材料在2 mA/cm2的电流密度下比电容为1175 mF/cm2;当电流密度升高至20 mA/cm2时,其比电容仍保持在1068 mF/cm2;并且在15 mA/cm2的电流密度下循环5000后仍保留了97.1%的初始电容,且各项电化学性能均高于CC@Co3O4,这意味着多级结构和双金属体系的引入使复合材料的性能得到了极大提升。

In order to enhance actual capacitance of Co3O4,a hierarchically structure of bimetallic Ni-Co composite material was designed.The cobalt carbonate hydroxide nanosheets were grown in situ on carbon fiber cloth(CC@CCH NS)by hydrothermal method;then the layered nickel-cobalt double hydroxide was grown on cobalt carbonate hydroxide nanosheets by electrodeposition.After annealing the CC@CCH NS@NiCo LDH,a hierarchically structure CC@Co3O4@NiCo2O4 composite material was obtained.The characterization indicated that CC@Co3O4@NiCo2O4 composite has a specific capacitance of 1175 mF/cm2 at a current density of 2 m A/cm2;when the current density increases to 20 mA/cm2,the specific capacitance remains at 1068 mF/cm2;After for cycling 5000 times at a current density of 15 mA/cm2,97.1%of the initial capacitance is retained,and the electrochemical performance are higher than that of CC@Co3O4,which means that the introduction of hierarchically structure and bimetallic system makes the composite performance greatly.