Growth of carbon nanofibers on aligned zinc oxide nanorods and their field emission properties

Carbon nanofibers were grown by electrodeposition technique onto aligned zinc oxide (ZnO) nanorods deposited by hybrid wet chemical route on glass substrates. X-ray diffraction traces indicated very strong peak for reflections from (0 0 2) planes of ZnO. The Raman spectra were dominated by the presence of G band at about 1597cm(-1) corresponding to the E-2g tangential stretching mode of an ordered graphitic structure with sp(2) hybridization and a D band at about 1350cm(-1) originating from disordered carbon. Fourier transformed infrared studies indicated the presence of a distinct characteristic absorption peak at similar to 511cm(-1) for Zn-O stretching mode. Photoluminescence spectra indicated band edge luminescence of ZnO at similar to 3.146 eV along with a low intensity peak at similar to 0.877 eV arising out of carbon nanofibers. Field emission properties of these films and their dependence on the CNF coverage on ZnO nanorods are reported here. The average field enhancement factor as determined from the slope of the FN plot was found to vary between 1x10(3) and 3x10(3). Both the values of turn-on field and threshold field for CNF/ZnO were lower than pure ZnO nanorods. (C) 2010 Elsevier B.V. All rights reserved.