Synthesis, electronic structures and luminescent properties of Eu3+ doped KGdTiO4

Abstract

Eu³⁺-activated layered perovskite ionic conductor KGdTiO₄ red emitting phosphors to be used for ultraviolet based light emitting diodes (LEDs) and field emission displays (FEDs) were successfully synthesized by a modified sol–gel method. The electronic structure of KGdTiO₄ was estimated by density functional theory (DFT) calculation. The phase purity and luminescent properties of the samples were characterized by X-ray diffraction (XRD), photoluminescence excitation (PLE) and emission (PL) spectra. The cathode-luminescence (CL) spectra of the phosphors as a function of the accelerating voltage and filament current were also measured. In addition, the thermally stable phosphors are investigated according to their temperature-dependent PL spectra and decay curves. The Eu³⁺ doped KGdTiO₄ phosphor offers higher brightness and thermal stability, and shows great potential for application in LEDs and FEDs as a suitable red-emitting phosphor.