▎ 摘　　要

The current study demonstrates field emission response of nickel cobalt oxide (NCO) nanostructures-graphene oxide (GO) hybrid. NCO nanostructures were synthesized directly on Ni substrates by hydrothermal method and GO was synthesized by modified Hummer's method. The as-synthesized nanostructures were characterized to determine phase, morphology, composition, and work function. The bare, one-dimensional (1D) needle-like nanostructure of NCO showed a low field emission response. Turn-on fields for NCO were 5.8 V/mu m and 6.0 V/mu m for foam and foil substrates, respectively. By making a hybrid of GO layers on top of the NCO nanostructure, the field emission response was found to enhance abruptly. The turn-on field was reduced down to 2.9 V/mu m the hybrid structure from a high value of 6.1 V/mu m. Maximum emission current density of the NCO foil and NCO foam was 90 and 132 mu A/cm(2), respectively. After depositing GO on these samples, maximum current increased to 1090 and 2360 mu A/cm(2), respectively. The combination of 1D and 2D nanostructure offers a modified surface, leading to a change of local field concentration and enhanced field emission. Surface modification by the deposition of GO on the NCO nanostructure led to enhancement of field emission response.