关键词: 电极, 电容量, Co₃O₄, 纳米线, 丙三醇

Abstract: Cobalt oxide (Co₃O₄) nanowires were controllably synthesized using glycerol and Co(NO₃)₂ as reagents and adjustment of the experimental parameters. The morphology and structure of the asprepared products were characterized by a series of techniques such as X-ray podwer diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Electrochemical performance of the nanowires was studied by cyclic voltammetry (CV) and galvanostatic charge-discharge measurements. It was found that two pairs of redox peaks appeared in the CV curves of Co₃O₄ nanowire electrodes at low scan rates. The specific capacitance of the Co₃O₄ nanowire electrodes was 163 F·g^-1 at a current density of 1 A·g^-1, according to the galvanostatic charge-discharge measurements. Cycle stability tests showed that the specific capacitance increased over the first tens of cycles and then reduced slowly. After 1000 cycles, the capacitance retention was over 98% at 1 A·g^-1 and 80% at 4 A·g^-1; it then decreased obviously with further increase in cycle number. In Li-ion battery measurements, Co₃O₄ nanowire electrodes showed a discharge capacitance of 1124 mAh·g^-1 which decreased rapidly during the cycle test. The formation mechanism and the relationship between the structure and electrochemical properties of Co₃O₄ nanowires were discussed based on the experimental results.

Key words: Electrode, Capacitance, Co₃O₄, Nanowire, Glycerol