Realizing Bright Blue-Red Color-Tunable Emissions from Gd 2GeO 5:Bi 3+Eu3+ Phosphors Through Energy Transfer Toward Light-Emitting Diodes

Abstract

Novel Bi³⁺/Eu³⁺ ions co-doped Gd₂GeO₅ (GGO) phosphors were prepared by a high-temperature solid-state reaction method. X-ray diffraction, photoluminescence, and CIE chromaticity coordinates were applied to analyze the as-obtained phosphors. The as-prepared GGO:Bi³⁺,Eu³⁺ phosphors showed color-tunable emissions from blue (Bi³⁺) to red (Eu³⁺) with increasing the Eu³⁺ doping concentration via a high-efficiency energy transfer process. Moreover, the mechanism of energy transfer from Bi³⁺ to Eu³⁺ ions was the dipole-quadrupole interaction. All these meaningful results demonstrated that blue-red color-tunable GGO:Bi³⁺,Eu³⁺ phosphors have potential applications in white light-emitting diodes (LEDs) and plant growth LEDs.