Ag/carbon nanofibers and carbon nanofibers were prepared through electrospinning and high temperature carbonization. The catalyst was investigated through oxidation of styrene. The highest conversion of styrene respectively got to 98% and 70% when calcination temperature got to 1200 degrees C. CNFs (carbon nanofibers) have not only excellent catalytic performance but also relatively large accessible ion surface area to accommodate greater capacity and high graphitization degree to accelerate ion diffusion. CNFs exhibited excellent electrochemical performance for use as supercapacitors with high specific capacity of 271.1 F g(-1) at current density of 0.5 A g(-1), good rate capability and superior cycling stability over 3050 cycles.