Regulated morphology of ScF₃: Eu³⁺, Bi³⁺ microcrystals: Microwave-assisted hydrothermal synthesis, structure and luminescence properties

A facile microwave-assisted hydrothermal method has been employed to synthesize a series of ScF₃: x Eu³⁺, y Bi³⁺ (x = 0 −0.20, y = 0–0.05) crystals to improve the fluorescence performance by optimizing the concentrations of Eu³⁺ ions and Bi³⁺ ions. The as-obtained products then were characterized by thermal field emission scanning electron microscope (FE-SEM), X-ray powder diffractometer (XRD), high resolution transmission electron microscope (HRTEM), and photoluminescence (PL) spectrometer, systematically. The results manifest that the reaction temperature and reaction time play an significantly important role on the morphologies and sizes of the as-prepared products. Furthermore, the optical properties of ScF₃: x Eu³⁺, y Bi³⁺ samples was investigated in detail. The emission spectra of ScF₃: x Eu³⁺ recorded upon the excitation wavelength of 394 nm showed a strong emission peak located at 592 nm, which is corresponding to the magnetic dipole of the ⁵D₀–⁷F₁ transition of Eu³⁺ ions. Additionally, it was found that the luminescence of the samples has been deeply enhanced after the addition of an appropriate amount of Bi³⁺. The opportune concentration of Eu³⁺ and Bi³⁺ are x = 0.10 and y = 0.02, respectively.