Photoacoustic spectra of BaFBr:Eu2+ phosphors Original Research Article

The photoacoustic (PA) technique was used to study the properties of storage phosphors. The excited state energy levels of Eu2+ in BaFBr crystal were studied and the structure of the excited energy levels was revealed in the PA spectra. With the phase shift of PA signal of this material, the de-excitation processes of Eu2+ were also studied. By this, the relative emission efficiencies of different excited states were found in the order: 6P > 6I > 6D. The photostimulated luminescence (PSL) de-excitation process exist some fast non-radiation processes, which conform to the model of Von Seggern. The PA spectra of BaFBr:Eu phosphors synthesized in different conditions were studied and the best quality condition was sintered in 5% H2-N2 atmosphere.