Investigation of photoluminescence and dielectric properties of europium-doped LaOCl nanophosphor and its Judd–Ofelt analysis

Present Phosphor La_1−xEu_xOCl (0 ≤ x ≤ 0.09) was synthesized via conventional solid-state method at a temperature of 700 °C for a duration of 2 h. The compound crystallized in the tetragonal structure with space group P4/nmm (No. 129). The intensity of transition ⁵D₀ → ⁷F₂ (617 nm) was found to be more intense in the photoluminescence spectra. Intensity parameters and radiative properties like radiative lifetime, transition probabilities, and branching ratio are evaluated employing of the Judd–Ofelt theory. At room temperature for a frequency range of 10 Hz—8 MHz, AC conductivity, dielectric properties of La_1−xEu_xOCl (0.01 ≤ x ≤ 0.09) are studied. Studies indicate that above 30 kHz till100 kHz, the AC conductivity establishes slowly and at 300 kHz increases rapidly. Greater values of dielectric constant and loss were exhibited towards lower frequencies which then declined significantly with increasing frequency making the phosphor suitable for microwave device applications. The CIE color coordinates results of Eu³⁺-activated LaOCl phosphor (0.642, 0.358) were closer to the commercial red phosphors such as Y₂O₃:Eu³⁺(0.645, 0.347), Y₂O₂S:Eu³⁺ (0.647, 0.343) and National Television System Committee (NTSC) (0.67, 0.33) resulting in making LaOCl:Eu³⁺behaves as a promising material for red phosphor materials.