Title
Thermally stable Ca2Ga2SiO7:Tb3+ green emitting phosphor for tricolor w-LEDs application
Author
Kusum Rawat, Amit Kvishwakarma, Kaushal Jha
Year
2020
Journal
Materials Research Bulletin
Abstract
A series of Tb3+ doped Ca2Ga2SiO7 were successfully prepared by conventional solid-state reaction technique and characterized via X-ray diffraction (XRD), photoluminescence excitation and emission spectra, and luminescent decay curve. XRD analysis revealed the presence of a single phase tetrahedral structure of Ca2Ga2SiO7 belonging to P4¯21 m space group. The emission spectra revealed peaks arising from both 5D3 and 5D4 level under the most intense excitation of 374 nm, and the emission color varied from blue to green via greenish-yellow by altering the Tb3+ concentrations. The energy transfer interaction between Tb3+ ions was dipole-dipole in nature, as evident from the Dexter theory and Inokuti- Hirayama model. The emission intensity remained at 95.28 % and 86.30 % of the initial value at 398 K and 498 K for the optimized sample, respectively indicating strong thermal stability. The results mentioned above indicated that Tb3+ doped thermally stable Ca2Ga2SiO7 has potential application in the w-LEDs.
Instrument
FP-8500
Keywords
Fluorescence, Photoluminescence, Quantum yield, Chemical stability, Quenching, Color analysis, Materials