Summary: | 碩士 === 南台科技大學 === 化學工程與材枓工程系 === 97 === In the study, the SrAl2O4: Eu2+ phosphors was prepared by a new sol-gel method, the solid-state reaction method and the modified solid-state reaction method. According to the experimental results, the pre-treated temperature affects the emission intensity of the phosphor powder. The best formation method to synthesize SrAl2O4: Eu2+ phosphor is the sol-gel method. The best formation condition is pre-treated at 900℃ and then calcined at 1300℃in 10%H2/90%He atmosphere. In addition, the different pre-treated temperature can cause the difference shape of powder. The morphology of powders were spherical particles for low treated temperature, but the powder were changed to plate and fiber like particles for high pre-treated temperature.
Increasing Al/ Sr=6, the product contains SrAl4O7 and SrAl12O19 phases. If Al/ Sr=12 , the product is SrAl12O19 phase with minor SrAl2O4 and SrAl4O7 phase. The mixing phases was induced the two emission band which provided to change the color of phosphor to obtain similar white light by change Al/Sr ratio. The particles morphologies were changed from spherical to plate and fiber like by changing Al/Sr ratio. In this study , we used this idea to form a plate like alumina by adding small amount of strontium(Sr) in to boehmite(the starting material of alumina).
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