Abstract:
Undoped and copper doped zinc oxide (ZnO) nanorods have been synthesized by a simple
chemical bath deposition (CBD) method at a temperature of 90 C. Structural, morphological,
optical and electrical properties of the synthesized ZnO nanorods were found to be
dependent on the Cu doping percentage. X-ray diffraction (XRD) patterns revealed strong
diffraction peaks of hexagonal wurtzite of ZnO, and no impurity phases from metallic zinc
or copper. Scanning electron microscopy (SEM) images showed changes in diameter and
shape of nanorods, where by those doped with 2 at.% and 3 at.% aggregated and became
compact. Selected area electron diffraction (SAED) patterns indicates high quality, single
crystalline wurtzite structure ZnO and intensities of bright spots varied with copper
doping concentration. UVevisible absorption peaks of ZnO red shifted with increasing
copper doping concentration. Raman studies demonstrated among others, strong and
sharp E2 (low) and E2 (high) optical phonon peaks confirming crystal structure of ZnO.
Current-voltage measurements based on the gold/ZnO nanorods/ITO showed good rectifying
behavior of the Schottky diode. The predicted Schottky barrier height of 0.60 eV was
obtained which is not far from the theoretical Schottky-Mott value of 0.80 eV