Optical and structural properties of ZnGa2O4: Eu3+ nanophosphor by hydrothermal method

Nanophosphor of ZnGa2O4:Eu3+ was synthesized through a hydrothermal method. The particle size was about 20 nm confirmed by X-ray diffractometry and scanning electron microscopy. Excitation peaks attributed to the charge transfer of Eu-O were redshifted to longer wavelength sides. Red emission peaks originating from D-5-F-7(j) (j = 0-6) transitions of Eu3+ were split into two sub-bands, indicating that two different Eu3+ ions exist at tetrahedral Zn2+ and octahedral Ga3+ sites. Relative intensities of two sub-bands were different from those of bulk phosphor. The color purity of ZnGa2O4:Eu3+ nanophosphor is enhanced in comparison with that of bulk phosphor. Optical characteristics of ZnGa2O4:Eu3+ nanophosphor can be explained by different site occupancy of Eu3+ from ZnGa2O4:Eu3+ bulk phosphor. (c) 2006 Elsevier B.V. All rights reserved.