Photoluminescence, photocatalysis and Judd-Ofelt analysis of Eu3+-activated layered BiOCl phosphorsElectronic supplementary information (ESI) available. See DOI: 10.1039/c4ra10163d

Eu 3+ -activated layered BiOCl phosphors were synthesized by the conventional solid-state method at relatively low temperature and shorter duration (400 °C for 1 h). All the samples were crystallized in the tetragonal structure with the space group P 4/ nmm (no. 129). Field emission scanning electron microscopy (FE-SEM) studies confirmed the plate-like morphology. Photoluminescence spectra exhibit characteristic luminescent 5 D 0 → 7 F J ( J = 0-4) intra-4f shell Eu 3+ ion transitions. The electric dipole transition located at 620 nm ( 5 D 0 → 7 F 2 ) was stronger than the magnetic dipole transition located at 594 nm ( 5 D 0 → 7 F 1 ). The evaluated Commission International de l'Eclairage (CIE) color coordinates of Eu 3+ -activated BiOCl phosphors were close to the commercial Y 2 O 3 :Eu 3+ and Y 2 O 2 S:Eu 3+ red phosphors. Intensity parameters ( Ω 2 , Ω 4 ) and various radiative properties such as transition probability ( A tot ), radiative lifetime ( τ rad ), stimulated emission cross-section ( σ e ), gain bandwidth ( σ e × Δ λ eff ) and optical gain ( σ e × τ rad ) were calculated using the Judd-Ofelt theory. The experimental decay curves of the 5 D 0 level in Eu 3+ -activated BiOCl have a single exponential profile. In comparison with other Eu 3+ doped materials, Eu 3+ -activated BiOCl phosphors have a long lifetime ( τ exp ), low non-radiative relaxation rate ( W NR ), high quantum efficiency ( η ) and better optical gain ( σ e × τ rad ). The determined radiative properties revealed the usefulness of Eu 3+ -activated BiOCl in developing red lasers as well as optical display devices. Further, these samples showed efficient photocatalytic activity for the degradation of rhodamine B (RhB) dye under visible light irradiation. These photocatalysts are useful for the removal of toxic and non-biodegradable organic pollutants in water. Crystal structure of tetragonal BiOCl, field emission scanning electron micrographs, CIE chromaticity diagram and percentage of RhB dye degradation of Bi 1− x Eu x OCl.