The effect of Mn2+ doping on strcuture and photoluminescence of ZnO nanofilms synthesized by sol-gel method

Mn-doped ZnO nanocrystallite thin films with different Mn contents were synthesized by sot-gel method. Thermal annealing processes in N-2 ambient at 500 degrees C were employed to improve the film quality. Physical properties were investigated using XRD, PL and EPR. XRD spectra show all the films are hexagonal wurtzite structures and diffraction peaks shift to the big angle with increasing Mn content, which indicates that Mn has entered the ZnO lattice and substituted the Zn site. Small quantity of manganese oxide phase also presents in the spectra. Room-temperature photoluminescence spectra show the ultraviolet emission shift to low-energy side with the increasing Mn content, and the defect-related emissions were passivated by manganese oxide. EPR pattern indicates that Mn2+ exist in ZnMnO system. (c) 2006 Elsevier B.V. All rights reserved.