Corollary of Energy Transfer On Luminescence From Ce3+ / Eu3+ Co-Activated Glasses For White Light-Emitting Diodes

Abstract

A series of singly and doubly Ce3+ / Eu3+ doped lithium borate (LBZ) glasses have been synthesized via melt quenching. XRD and SEM analysis confirmed the non-crystalline nature of glasses. The emission spectrum of Ce3+: LBZ glass reveals an extensive blue emission band at 447 nm (5d→4f) by exciting with 350 nm. An intense excitation band noticed at 393 nm (7F0→5L6) of Eu3+ in Eu3+: LBZ glass, which is associated with the excitation wavelength of near-ultraviolet LED chip. The luminescence spectra of Eu3+ disclose a strong red emission at 612 nm (5D0→7F2) excited with 393 nm. By raising the content of Eu3+ ions, the luminescence features were embellished remarkably. However, the dazzling red emission intensity of Eu3+ was ameliorated by the insertion of Ce3+ ions in co-activated glass due to energy transmission. Spectral overlap, fluorescence studies, decay dynamics, CIE coordinates and color purity corroborated the transfer of energy from Ce3+ to Eu3+. The CIE color coordinates of the optimized (1.0 Ce3+ + 1.0 Eu3+) co-doped glass has been shifted to the white light region. In view of these spectral features, 1.0 mol % Ce3+ + 1.0 mol % Eu3+: LBZ glass could be suggested as a promising candidate for the white light applications.