Elucidating the electronic structures and photoluminescence properties of single-phase ScF₃:Dy³⁺, Eu³⁺, Ce³⁺ phosphors for LEDs

A series of single-component ScF₃:Dy³⁺, Eu³⁺, Ce³⁺ phosphors prepared by means of microwave hydrothermal method were explored for light-emitting diodes. The as-prepared samples were characterized via X-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence (PL) spectroscopy. In order to rationalize the experimental results, first-principle calculations based on density functional theory had been carried out to discover electronic structures. PL performance of the RE³⁺-doped phosphors exhibited well-defined bands in the visible region. By adjusting the ratios of Ce/Dy/Eu, the color of the as-prepared phosphors can vary from blue (0.24, 0.23) to red (0.51, 0.30) across the white (0.34, 0.26) region according to the chromaticity coordinates. The results suggested that the Dy/Eu/Ce-doped ScF₃ might act as down-convert phosphors for near ultraviolet light-emitting diodes, especially for white LEDs. What is more, it can also promote a deep comperhension of the relationship between structure and properties in ScF₃-based phosphors. [Figure not available: see fulltext.].