Doping introduce nucleation site barrier in ZnO nano/micro rod arrays film grown by chemical bath deposition

Abstract

ZnO nano/micro rod arrays (N/MRAs) thin films were grown on ZnO nuclei layer using chemical bath deposition technique via mixed degree of supersaturation. In the present work, the interface energy barrier introduced by Mn doping confine the nucleation site is decisively investigated. Hexagonal wurtzite crystal structure of pure and Mn doped ZnO N/MRAs is clearly confirmed by structural and optical characterization techniques (X-ray diffraction and µ-Raman). From XRD spectra, it is shown that the preferentially oriented (002) diffraction peak changed to (100) by Mn doping that indicates the stacked crystallographic planes are produced under nucleation sites barrier. Scanning electron microscopic (SEM) images of ZnO N/MRAs clearly shows the ZnO microrods (MRs) are aligned on ZnO nanorods (NRs). By Mn doping, the ZnO N/MRAs converted into microcrystalline structures including rods and spherulitic under changing mixed degree of supersaturation. The Mn ions in ZnO N/MRAs is confirmed by energy dispersive X-ray spectroscopic analysis (EDX).The band gap energy value and atomic level defect states of pure and Mn doped ZnO N/MRAs are calculated and analyzed using UV–vis absorption and photoluminescence spectra respectively.