We report the preparation and photoluminescence spectral analysis of Tb3+ and Eu3+ doped Zn2SiO4 powders in sol-gel sol-gel process. On exposure to an UV source, these rare earth ions doped zinc silicate materials have shown prominent luminescent green and red colors, due to the electronic transitions of 5D4 yields 7F5 (Tb3+) and 5D0 yields 7F2 (Eu3+) respectively. The green emitting transition of Tb3+ material has been a magnetic dipole in nature and the red emitting transition of Eu3+ material has been due to an electric dipole in nature with a hypersensitivity in its luminescence. Systematic characterization has been carried out to understand the fluorescence efficiency of these two materials by measuring their excitation, photoluminescence, time-resolved luminescence spectra and lifetimes of the emission transitions (5D0 yields 7F0,1,2,3,4&5) of Eu3+ at two different excitation wavelengths of 226 nm and 395 nm. However, for the emission transitions (5D4 yields 7F6,5,4,3,2&1) of Tb3+ doped material, one excitation wavelength of 229 nm was used. Structural characteristics of these materials was carried out with an XRD and TEM measurements. The computed color coordinates suggest that both the phosphors have all desirable features for CRT screen applications.
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