Optical, structural and morphological studies of (ZnO) nano-rod thin films for biosensor applications using sol gel technique

Uniformly distributed ZnO nano-rods (NRs) with diameters in nano-scale have been successfully grown in two stages; the first at annealing temperature (250–300 °C) for seed layer preparation on glass substrate by using sol gel technique and the second at low temperature (90–95 °C) by aqueous chemical growth (ACG) method. The same prepared thin film samples were grown on the surface of silver wire (0.25 mm in diameters) to produce electrochemical nano-sensors. The structure and the morphology of the prepared samples will be evaluated using XRD, Scanning electron microscope SEM.The absorption coefficient (α) and the band gap (Eg) for ZnO NRs thin films were determined. (α) was decreased by increasing the annealing temperature due to the increase of the surface roughness caused by higher temperature, where the creation of surface roughness gives rise to multi-reflections which, capture the reflected radiation and enhance the absorptivity.We are presenting an iron ion (Fe3+) potentiometric sensor based on functionalized ZnO nano-rods with selective iono-phore (18 crown 6). Zinc oxide nanorods (NRs) thin films with a diameter of about 68 up to 94 nm were grown on silver wire and gold coated glass.