Templated one step electrodeposition of high aspect ratio n-type ZnO nanowire arrays.

High aspect ratio Zinc Oxide (ZnO) nanowires (NWs) were synthesized by template based one-step electrochemical deposition (OSECD) technique. The electro-reduction of hydroxide ions in the presence of Zn(2+) ions within Zn(NO(3))(2) is involved in the growth of ultra thin NWs arrays. Field Emission Scanning Electron Microscopy (FESEM) images revealed that the growth rates of different crystal faces, (0 0 0 1) and (0 0 0 1), were different at different deposition potential for the high aspect ratios ZnO NWs arrays. The n-type semiconductor conductivity of ZnO NWs was ascertained by a Hot-Probe approach. X-ray diffraction results demonstrated that the grown ZnO NWs had wurtzite crystal structure with unit cell parameters a=2.93 A, c=5.45 A and a deterioration of preferred (1 0 1) orientation is observed at more negative deposition potentials. Small angle X-ray scattering (SAXS) results evidenced that the NW arrays grown at -1.2 V have higher fraction of larger crystallites. Micro-Raman spectroscopy analysis showed that the variation in E(2) (high) vibration mode at 435 cm(-1) is coupled with an increase in electro acceptor oxygen atoms incorporated within ZnO NWs at -1.2 V. Copyright 2009 Elsevier Inc. All rights reserved.