Aligned Zinc Oxide nanorods by hybrid wet chemical route and their field emission properties

Aligned Zinc Oxide (ZnO) nanorods were deposited by hybrid wet chemical route onto glass substrates with pre-deposited ZnO seeds produced by sputtering a ZnO target in argon plasma. X-ray diffraction trace indicated very strong peak for reflections from (002) planes of ZnO. Photoluminescence spectra for the films were dominated by a strong luminescence peak in the yellow-green region (∼ 654 nm) at room temperature. The peak intensity slightly diminished when recorded at 8 K but the peak positions remain invariant. The Raman spectra were dominated by the presence of a strong peak located at ∼ 437 cm-1 arising due to E2 mode of ZnO followed by peaks at ∼ 331 cm-1 for second order Raman vibration and 379 cm-1 for A1 mode of ZnO. Fourier transformed infrared studies indicated the presence of a distinct characteristic absorption peaks at 500 cm-1 for ZnO stretching modes. Field emission properties of these films and their dependence on the deposition parameters are reported here. Work function (φ) values obtained from the Fowler-Nordheim model varied between 5.2 and 5.3 eV while the field factor (β) varied between 305 and 610. The critical field was found to vary between 12 and 24 V/μm