Luminescence Studies On Dy3+:Tb3+ Codoped Borophosphate Glasses For WLED Applications

Dy3+:Tb3+ codoped borophosphate glasses with the chemical composition 60B(2)O(3)+(19.5-x)P2O5+10Na(2)O+10NaF+0.5Dy(2)O(3)+xTb(2)O(3) (where x= 0.1, 0.5, 1 and 2 in wt %) have been synthesized following the melt quenching technique. The fall in emission intensity and lifetime value of the Dy3+ ions with increasing Tb3+ ions concentration indicates the energy transfer process takes place between the Dy3+ and Tb3+ ions. The non- exponential decay profile of the F-4(9/2) state pertaining to the Dy3+ ions were well fitted with S=6 of IH model thus indicates the dipole-dipole type of interaction takes place between the Dy3+ and Tb3+ ions. Among the prepared glasses, BPD0.5T glass exhibit better colour coordinates (0.336, 0.358) and colour correlated temperature (CCT) value (5766 K) and the same is suggested as a potential candidate for cool white light applications.