Synthesis, characterization and spectroscopic properties of some rare earth activated LiAlO2 phosphor

The current paper comprises the synthesis of LiAlO2 phosphor doped with rare-earth elements Tb3+, Eu3+, and Dy3+ by microwave-assisted solution combustion synthesis method (SCS) and the spectroscopic properties were examined. The phosphors samples were identified and characterized by XRD, FT-IR, thermo-gravimetric analysis TG-DTA and SEM. All the prepared phosphors show polycrystalline nature with a grain size of about 49 nm as confirmed from XRD and SEM. Photoluminescence excitation and emission spectrum of Tb3+, Eu3+, and Dy3+ doped LiAlO2 with different sintering temperature and concentration of dopants were investigated. The Dy3+ shows the strongest blue emission peak at 484 nm corresponding to the transition 4F9/2 to 6H15/2 under UV excitation of 358 nm. The Eu3+ doped LiAlO2 phosphor shows emission peak 591 nm to 615 nm for UV excitation of 238 nm which arise due to 5D0 to 7F1 electric dipole transitions. The Tb3+ doped phosphor shows a broad excitation peak centered at 238 nm whereas it exhibits an emission peak at 544 nm corresponding to the peak transition 5D4-7F6 under the UV excitation at 238 nm.