Luminescence properties of Tm³⁺/Dy³⁺ co-activated borate and borophosphate glasses for near daylight w-LED and dosimetry application

The melt-quenching technique was used to synthesize Tm3+/Dy3+ co-doped glasses, which were then characterized using various spectroscopic techniques. For the glasses, the direct and indirect optical band-gap energies from Tauc's plot, as well as the Urbah energy (E-u), were calculated. The PL emission spectra show the radiative transitions of Dy3+ ions from F-4(9/2) result in emissions at 484, 578, and 669 nm, and transition of Tm3+ ions from D-1(2) results in emissions at 452, 476, and 520 nm in Tm3+/Dy3+ borate glass (TDB) and Tm3+/Dy3+ borophosphate glasses (TDBP). The non-single exponential nature of the decay of the present glasses was studied by fitting with the Inokuti-Hirayama model, and the energy transfer (Q) and other related parameters were calculated. The results of the calculated colorimetric parameters, the value of the yellow-to-blue (Y/B) luminescence intensity ratio, and the TL kinetic parameters by the peak shape method show that both TDB and TDBP glasses are promising multifunctional materials.