One-step hydrothermal synthesis of Sc2Mo3O12:Ln3+ (Ln = Eu, Tb, Dy, Tb/Eu, Dy/Eu) nanosheets and their multicolor tunable luminescence

Abstract

Novel Sc₂Mo₃O₁₂:Ln³⁺ (Ln = Eu, Tb, Dy, Tb/Eu, Dy/Eu) phosphors have been synthesized via a one-step hydrothermal route using glycine (Gly) as a surfactant. The phosphors were characterized using X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), and luminescence decays. It was found that various surfactants had a profound influence on the crystal phase, morphology and emission intensity of the final products. Furthermore, the photoluminescence of Ln³⁺-doped Sc₂Mo₃O₁₂ phosphors (Ln = Eu, Tb, Dy, Tb/Eu, Dy/Eu) was studied in detail. The energy transfer of MoO₄²⁻ → Tb³⁺ (Dy³⁺) → Eu³⁺ and multicolor tunable emission occurred by changing the ratio of Tb³⁺/Eu³⁺ or Dy³⁺/Eu³⁺ under single wavelength excitation. Moreover, the energy transfer mechanism from Tb³⁺ (Dy³⁺) to Eu³⁺ was ascribed to dipole–dipole interactions and the energy transfer efficiency from Tb³⁺ to Eu³⁺ (95.3%) was higher than that from Dy³⁺ to Eu³⁺ (87.5%). Their tunable multicolor luminescence properties make Sc₂Mo₃O₁₂:Ln³⁺ (Ln = Eu, Tb, Dy, Tb/Eu, Dy/Eu) phosphors suitable for many potential applications in the fields of color displays and fluorescent lamps.