| Photoluminescence spectrum of ZnO nanomaterials include near UV spectrum andvisible spectrum generally. The luminescence properties have closely contact with thecrystalline quality of ZnO nanomaterials. ZnO prepared by PLD emits ultraviolet lightstronger than visible light generally. As so many defects, ZnO nanorods have a strong visibleemission. The preparation process of ZnO nanorods is simple, and it has low reactiontemperature, pollution-free, and so on. As the base material of white LED it can be widelyused in lighting and display field. For the purpose of obtained ZnO nanorods which havestrong visible emission. In this paper, ZnO nanorods are prepared by hydrothermal methodand ZnO thin films are by PLD, respectively. Effects of several of growing conditions andpost-processing on structure and photoluminescence properties of ZnO nanomaterials haveinvestigated.⑴Effects of different substrates on growth ZnO nanorods which prepared by PLDcombine with hydrothermal method are studied. The crystallization of ZnO nanorods whichprepared on the glass substrate with ZnO film buffer layer is the better than others. It can beseen from room temperature photoluminescence spectra that visible light emission of ZnOnanorods stronger than ZnO film. On the basis of the fact, the influence of different growthconditions for ZnO nanorods structure and luminous are studied. ZnO nanorods which visiblelight emition much stronger are expected.Through the preparation of ZnO nanorods with different reaction time, different solutionconcentration and different reaction temperature the growth mechanism of ZnO nanorods arestudied and the role of ZnO film buffer layer in the growth process of ZnO nanorods isexplored.①In the2-5hour range during the growth, as the reaction time increases, relativeintensity values of the diffraction peak of ZnO nanorods are increased, the FWHM aredecreased. It shows that the crystalline quality of ZnO nanorods is getting better. ZnOnanorods have uniform distribution, compacted arrangement from the state of unevendistribution and big gap. Room temperature PL spectra display the near band edge emission ofZnO nanorods is reduced while the deep level luminescence is increased.②In the reactionsolution concentration range of0.03mol/L-0.06mol/L, as the solution concentration increases,the diameter of ZnO nanorods are increase, the gap are decrease, and its uniformity is getting better. The near band edge emission of ZnO nanorods are increases first and then decreases,deep level luminescence shows an increasing to constant trend. The ratio of the light emittingintensity gets lower in turn. It shows that the deep level luminescence of ZnO nanorods isincrease with solution concentration increased.③In the reaction temperature range95℃-125℃, as the reaction temperature increases, the diameter of ZnO nanorods are increasegradually, the gap are decrease, the orientation of nanorods become better, the near band edgeemission of the ZnO nanorods first decrease and then increase and deep level luminescenceincrease gradually.④The ZnO film buffer layer plays the role of seed layer and buffer layer,which prompt rapid nucleation and growth of ZnO nanorods, and inhibit ZnO nanorodsgrowing along the other phases.⑵At400℃substrate temperature, we prepared ZnO thin films with different oxygenenvironment by PLD. Effect of annealing on crystallization and luminescence of ZnO film arestudied.①Oxygen ionized did not appear in the preparation process. After annealing at500℃-900℃, FWHM of ZnO are reduced, but at900℃it increased suddenly, PL spectrashows that ZnO thin films appear luminescence peak in visible region after annealing, whilethe annealing temperature of800℃the luminescence intensity reached maximum.②Oxygenionized appear in the preparation process. PL spectra displayed luminescence peak appearedin the green light region. After annealing at500℃-900℃, FWHM of ZnO remained reduce, itbegan to increase at900℃; at800℃luminescence intensity value reached maximum invisible light region. |
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