Color-tunable photoluminescence and energy transfer properties of single-phase Sr₂MgSi₂O₇:Eu³⁺, Dy³⁺

Eu³⁺ and Dy³⁺ as activators in luminescence materials have been widely investigated because of their superior luminous properties. In this work, we synthesize Sr₂MgSi₂O₇:Dy³⁺, Sr₂MgSi₂O₇:Eu³⁺, and Sr₂MgSi₂O₇:Eu³⁺, Dy³⁺ in air via the solid-state reaction method. We research crystal phase and purity of all samples via XRD, discern their crystal structure and space-group, and investigate their luminescence properties. The yellow emission of Sr₂MgSi₂O₇:Dy³⁺ with emission spectrum in the range of 450–775 nm can be observed due to the ⁴F_9/2 → ⁶H_15/2, ⁶H_13/2, ⁶H_11/2, and ⁶H_9/2 transitions of Dy³⁺ ion. The red emission of Sr₂MgSi₂O₇:Eu³⁺ in the range of 550–725 nm is shown owing to the ⁵D₀ → ⁷F₁, ⁷F₂, ⁷F₃, and ⁷F₄ transitions of Eu³⁺ ion. Sr₂MgSi₂O₇:Eu³⁺, Dy³⁺ under excitation 388 nm shows yellow emission with chromaticity coordinates (0.3578, 0.3911) and glows red–orange light with chromaticity coordinates (0.5753, 0.3863) under excitation 394 nm. Sr₂MgSi₂O₇:Eu³⁺, Dy³⁺ can shows tunable emission when the ratio between Eu³⁺ and Dy³⁺ ions is changed. The energy transfer from Dy³⁺ to Eu³⁺ ions are known via the spectral features. Sr₂MgSi₂O₇:Eu³⁺, Dy³⁺ has a good thermal stability. Luminous mechanisms and energy transfer process of samples are analyzed by the energy level diagrams of Dy³⁺ and Eu³⁺ ions.