Porous carbon nanofibers (CNFs) with enhanced physical, thermal and morphological properties are desirable in many areas like catalyst support in fuel cells and supercapacitors as electrode material. This research addresses the effect of added nickel nitrate in 1, 3 and 5 wt% into polyacrylonitrile (PAN) precursor solution to produce CNF webs using electrospinning method. Based on the quantitative data obtained from field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) images, we can notice that CNFs were formed with diameters in the size range of 100-300 nm after carbonization at 1000 degrees C. Fiber diameter of the random CNFs was decreased by increasing the nickel nitrate contents along with dramatic improvements in porosity and specific surface areas. This study indicated that the optimal nickel nitrate concentration of 5 wt% has produced CNFs with enhanced physical and thermo-chemical properties. The high resolution X-ray diffraction (HR-XRD) showed an increase in intensity of 0 0 2 peak of the CNFs due to the catalytic function of nickel oxide in the carbonized web and these observations are in agreement with the thermal gravimetric data. Crown Copyright (C) 2009 Published by Elsevier B.V. All rights reserved.