Influence of Sintering Temperature on Judd–Ofelt Parameters and Emission Properties of Y₁.₉₆Al₀.₀₄O₃:Eu3⁺ Phosphor for n-UV Excited Red Emission Applications
摘要
This study reports on the synthesis and photoluminescence characterization of Y₁.₉₆Al₀.₀₄O₃:Eu3⁺ phosphors prepared via the nitrate combustion method and subsequently sintered at temperatures of 600 °C, 800 °C, and 1000 °C. Structural analysis confirmed the formation of a well-crystallized cubic Y₂O₃ phase, with increasing sintering temperature enhancing crystallinity. Under 254 nm excitation, intense red emission centered at 613 nm was observed, corresponding to the hypersensitive 5D₀ → 7F₂ transition of Eu3⁺. The Judd–Ofelt parameters (Ω₂ and Ω₄) were extracted using an developed web-based tool https://omasgroup.org/joes-software/#page-content which is Application software for complete Judd–Ofelt analysis from the emission spectrum of europium doped materials, which automates the conversion of emission intensity ratios into JO parameters, thereby streamlining the otherwise manual and error-prone calculation process, even for Eu3⁺ systems. Judd–Ofelt analysis, based on emission spectra, revealed that the intensity parameter Ω₂ increased with sintering temperature, indicating enhanced asymmetry around Eu3⁺ sites. The highest Ω₂ value (3.969 × 10⁻2⁰ cm2) and corresponding radiative transition probability A(5D₀ → 7F₂) of 269.91 s⁻1 were achieved at 1000 °C, along with an internal quantum efficiency of approximately 55%. These results demonstrate the strong influence of thermal treatment on the optical performance of the phosphor. The material’s enhanced radiative properties, high quantum efficiency, and structural stability suggest its potential for near-UV LED-pumped red-emitting applications in solid-state lighting and display technologies.