Influence of different synthesis methods on structure, morphology and luminescent properties of BiOCl:Eu³⁺ phosphors and J–O analysis

The BiOCl:Eu³⁺ phosphors were successfully synthesized by the solid state route and hydrothermal method, respectively. The influence of different synthesis methods on morphology and luminescent properties of BiOCl:Eu³⁺ phosphors was investigated by X-ray diffraction, Field emission scanning electron microscope, Raman spectra and photoluminescence spectrometer. Moreover, the BiOCl:Eu³⁺ structure was refined according to the Rietveld refinement method. The results indicated that BiOCl:Eu³⁺ phosphors synthesized by hydrothermal method were better than solid state method in terms of morphology and luminescence. The influence of pH was further investigated by hydrothermal method. It was found that the optimum condition of hydrothermal method was 160 °C, 10 h and pH = 6. In addition, Judd–Ofelt theory was employed to calculate the radiative parameters and optical properties such as intensity parameters (Ω₂, Ω₄), transition probability (A_R, A_N), radiative life time (τ), quantum efficiency (η), stimulated emission cross-section (σ_e) and gain bandwidth (σ_e × Δλ_eff). The calculation showed that the prepared phosphors possess longer lifetime and higher quantum efficiency. Significantly, the BiOCl:Eu³⁺ phosphors with better stimulated emission cross-section (σ_e) and gain bandwidth (σ_e × Δλ_eff) are suitable to apply in the field of optical display devices.