Morphology–luminescence correlations in europium-doped ZnO nanomaterials

In order to investigate the correlations of morphologies and optical properties, different morphologies of Eu-doped ZnO were synthesized by different methods. Specifically, the structure of SiO₂/ZnO:Eu nanoflower was synthesized for the first time and has not been reported previously. One percent was chosen as the Eu doping concentration. The relations of the morphology, diameter, and uniformity with the PL intensity were examined. The PL intensity of ZOE samples has a close relationship with the morphology. The PL intensity order of the different morphologies of ZnO:Eu is as follows: nanorod arrays > thin film > nanospheres > nanoparticles > nanoflowers > nanorods. The PL intensity of nanomaterials is larger, if the diameter of the nanomaterials is larger. However, the size of diameter is not the most important reason. It was found that the sample uniformity plays a key role on ZnO:Eu PL intensity. ZnO:Eu with small particle diameters may have strong photoluminescence intensity, if the nanoparticles are uniform.