Effect of the Concentration of Eu3+ Ions on Crystalline and Optical Properties of ZnO Nanowires

In this study, Eu 3+ -doped ZnO nanowires were prepared with different concentrations of Eu 3+ ions by a hydrothermal method.Before the Eu 3+ -doped ZnO nanowires were grown, sputtering was used to deposit ZnO films of ~300 nm thickness on SiO 2 /Si and glass substrates as the seed layer.Zn(NO 3 ) 2 -6H 2 O, Eu(NO 3 ) 3 -6H 2 O, and C 6 H 12 N 4 were used as reagents to grow the Eu 3+ -doped ZnO nanowires on ZnO/SiO 2 /Si and ZnO/glass substrates.First, the Eu 3+ -doped ZnO nanostructures were grown on the substrates at 100 ℃.We found that the nanowires could be successfully grown because an undoped ZnO solution was used, and the Eu 3+ -doped ZnO nanowires could not be grown because different concentrations of Eu 3+ ions were added.We also found that the required growth temperatures of the Eu 3+doped ZnO nanowires decreased with increasing concentration of Eu 3+ ions.In this study, we also thoroughly investigated the effects of different concentrations of Eu 3+ ions on the luminescence properties of the ZnO seed layer and the Eu 3+ -doped ZnO nanowires.We showed that the substrates used and the concentrations of Eu 3+ ions have considerable effects on the photoluminescence properties of the Eu 3+ -doped ZnO nanowires.