Preparation, Investigation And Application Of SrAl₂O₄ Luminescent Material

Kelly-emitting SrAl₂O₄, co-doped with Eu²⁺ and Dy³⁺ ions, is regarded as a useful phosphor that has good brightness, long persistent phosphorescence and greater chemical stability. Microwave assisted solid-state reaction is a new method for synthesizing inorganic materials by using microwave energy, which was known as an high efficient and quick, energy saving, heating-homogeneous, safe and clean method. In this paper, the SrAl₂O₄: Eu, Dy long afterglow phosphors were prepared by microwave assisted solid-state reaction synthesis. After been tested and approved eligible, the phosphor was introduced in the preparation process of luminous porcelain enamel.1. We offered a new synthesis route for SrAl₂O₄: Eu, Dy phosphor in this paper. Effect of synthesis route on the powder properties were assessed by means of X-ray diffractometer (XRD), scanning electron microscope (SEM), and a fluorescence spectrometer was used to detect the afterglow decay, excitation and emission spectra of the samples. The analytical results showed that, when the mole ratio of Sr: Al: Eu: Dy: B is 1:2:0.6:0.01:0.02, active carbon is used as microwave absorber and reducing agent, boric acid is used as flux, microwave power is 700W and heating time is 30 min, we could get nanometer SrAl₂O₄: Eu, Dy luminescent material.2. The SrAl₂O₄ phosphors prepared by microwave route and phosphors produced by traditional solid-state method were characterized by means of SEM, XRD and FL spectra separately, the differences between them were discussed as well. Compared with those synthesized by solid-state reaction process, the phosphors prepared by microwave route showed a smaller grain size, regular morphology and a clear blue shift occurred in the excitation and emission spectra. The results showed that the nanometer SrAl₂O₄ phosphor by microwave route could be applied extensively in many fields.3. By the craft of powder sieving, the obtained SrAl₂O₄ phosphor was used as phosphorescent pigment for the development of luminous porcelain enamel. The relevant performances of luminous porcelain enamel, like surface quality and luminous performance:, were characterized and discussed. The results showed that the luminous porcelain enamel produced by the microwave-prepared SrAl₂O₄ luminous powder has good brightness and surface quality.