Nickel-embedded carbon nanofibers were prepared by the processes of stabilization and carbonation after electrospinning a mixture solution of nickel acetate and polyacrylonitrile in N,N-dimethylformamide. The surface morphology and structure of composites were examined by scanning electron microscope (SEM) and X-ray diffraction (XRD). Compared with performances of composite electrodes with different mass ratios of nickel and carbon by cyclic voltammetry (CV) and chronopotentiogram test, the results show that the introduction of a proper proportion of nickel into carbon could enhance both specific capacitance (SC) and electrochemical stability. The specific capacitance of the carbon nanofiber electrode without the Ni loading was 50 F/g, while that of 22.4 wt.% Ni/carbon electrode increased to 164 F/g. The improved specific capacitance may be attributed to synergic effects from each pristine component, and the electrochemical catalysis effect of nickel. (C) 2008 Elsevier B.V. All rights reserved.