Photoluminescence properties of europium-activated double layered perovskite Sr3Ti2O7 for high-quality lighting applications

Abstract

We present a comprehensive investigation into the concentration and temperature-dependent photoluminescence (PL) properties of europium ion (Eu³⁺) activated double-layered perovskite Sr₃Ti₂O₇ materials. We conducted thorough analyses to assess their phase purity, crystal structure, surface morphology, and optical properties to gain a complete understanding. The double-layered perovskite Sr₃Ti₂O₇:Eu³⁺ exhibited a tetragonal phase with space group I4/mmm. When excited by 395 nm ultraviolet (UV) light, the prepared materials exhibited a firm red emission peak at 616 nm, indicating the hypersensitive electric dipole transition ⁵D₀ → ⁷F₂ in Eu³⁺ ions. The quantum yield of the optimized sample was estimated to be 18%. To explore the temperature-dependent behavior of the photoluminescence, measurements were carried out over a wide range of temperatures from 300 K to 450 K. Notably, the phosphors demonstrated significant thermal stability, with 75% of the emission intensity retained at 420 K compared to 300 K. These findings signify the material's ability to maintain its luminescent properties at elevated temperatures. The photometric characterization of Sr₃Ti₂O₇:Eu³⁺ further validated its red emission capability. Moreover, we employed the Judd–Ofelt approach to examine the radiative intensity parameters (Ω₂, Ω₄, Ω₆). The obtained results provide substantial support for the promising prospects of this perovskite material in the rapidly growing field of solid-state lighting and display devices.