Optical properties and carrier dynamics of CaSrSiO₄:Eu³⁺ phosphors prepared by using the solid-state reaction method

The optical properties and the carrier dynamics of CaSrSiO₄:Eu³⁺ phosphors synthesized by using a solid-state reaction method have been studied by means of scanning electron microscopy, X-ray diffraction, photoluminescence (PL), PL excitation, time-resolved PL, and PL quantum-yield measurements. The phosphor synthesized with a Eu concentration of 5% and sintered at 1380 °C for 2 h in air showed a high quantum yield of 88.53% and good CIE chromaticity coordinate values. The strong excitation bands observed at 395 nm (⁷F₀-⁵L₆) and 466 nm (⁷F₀-⁵D₂) lead to an intense ⁵D₀-⁷F₂ transition (614 nm). The forbidden transitions (⁵D₀-⁷F₀ and ⁵D₀-⁷F₂) were observed and showed lifetimes shorter than that of the magnetic dipole transition (⁵D₀-⁷F₁).