Carbon nanofibers (CNFs) with various structures were synthesized using electroplated nickel catalysts on diverse metal buffer layers via hot-filament chemical-vapor-deposition method. High-density thick CNFs were grown on copper and gold buffer layers whereas low-density thin CNFs were grown on chromium and titanium buffer layers. All CNFs revealed solid structure without hollow cores, and graphitic platelets of CNFs consisted of a mixed structure of stacked and herringbone arrangement. CNF films grown on gold buffer layers showed high-emission-current density and temporal stability: 170 mA/cm(2) at 7.3 V/mu m, and 10.3% fluctuation over 10 h at the current density of 6 mA/cm(2), respectively. (c) 2005 American Vacuum Society.