Study On The Process For Producing SrAl₂O₄: Eu²⁺, Dy³⁺ By Solid Phase Reaction

SrAl₂O₄: Eu²⁺, Dy³⁺ is a new functional material which was developed in the the 90's of the 20th Century. SrAl₂O₄: Eu²⁺, Dy³⁺ is a kind of aluminate system luminous materials which doped Eu, Dy into strontium aluminate, it have high performance. Rare-earth strontium aluminate luminous materials is free from radioactivity, nontoxic and harmless. The properties of this kind of material is so good that it have the largest output and applied range in the past few years. The rare-earth strontium aluminate luminous materials should be improved from three contents: 1.Luminous intensity is not large enough; 2. The number of colour is little; 3. The grain size of materials should be minish without losing luminous intensity. As a result, It is necessary to improve the process in order to uprate the luminescent properties of the rare-earth strontium aluminate luminous materials which will be applied extensively in a lot of professions.The luminance of luminous materials mostly depend on component element of host material and preparation technology conditions. The key of improving the luminescent properties is to choose right raw material and technological parameter properly.Firstly compare relative merits of different methods such as solid phase reaction, sol-gel preparation, microwave synthesis coprecipitation method, Hydriding combustion synthesis, and spray drying process through theoretical analyzing. To consider in the fields of environmental protection, prime cost and the luminance properpties of materials, preliminary choose solid phase reaction and microwave synthesis. Secondly trial-produce SrAl₂O₄: Eu²⁺, Dy³⁺ by solid phase reaction and microwave synthesis, test the luminance properpties of products. The luminance properpties of products made by solid phase reaction is further better than which made by microwave synthesis, so we decide to produe SrAl₂O₄: Eu²⁺, Dy³⁺ by solid phase reaction.Because of the important of uniformity of raw material when produce materials by solid phase reaction, we pretreated raw materisls in new ways, improve the uniformity effectively. Raw material was pretreated in new ways, then the rare-earth strontium aluminate luminous materials were produced by solid phase reaction method. The phase composition, excitation spectrum, emission spectrum and phosphorescence properties of luminous material were tested. To study influence of process conditions on luminescent properties of the rare-earth strontium aluminate luminous materials. The experimental results indicate that the pre-processing is premise of the synthesis of luminous material, new pre-processing improve luminescent properties of the rare-earth strontium aluminate luminous materials effectively, raw material ratio effect on phase composition and luminescent color, the sintering temperature and flux content effect on phase composition and luminescent properties. The species and contents of activating agent effect on excitation spectrum, emission spectrum and phosphorescence properties. The best component proportion of luminous materials were found after lots of trial and error, good technology has been gotten through many experimentations.