碱土铝酸盐蓄光型发光材料的后处理研究

采用胶体包覆和表面成膜包覆相结合的方法,对碱土铝酸盐蓄光型发光材料进行包覆后处理研究。分析了包覆后处理对材料表面结构变化、发光性能及应用性能的影响。研究表明:经过包覆后处理的发光材料在水中浸泡时,发光材料对水能保持稳定,水相的pH值和电导率保持基本稳定;而未经包覆后处理的发光材料在水中分解,其水相的pH值和电导率上升很快。经过包覆处理的SrAl_2O_4:Eu,Re(Re为稀土元素)(PLO)在水中浸泡720 h后能保持80％的初始亮度,未经处理的发光材料则失去发光性能。包覆后处理能在发光材料表面形成了一层连续的比较致密的保护层,有效地减少外界对发光材料的影响,而且可以修复发光材料颗粒原有的裂纹等缺陷。包覆处理后能有效提高发光材料的应用性能,如耐水性、分散性及耐高温性能,更能适应不同的应用领域。

STUDY ON THE POST-TREATMENT OF THE ALKALINE EARTH ALUMINATES LONG AFTERGLOW PHOSPHORS

Post-treating process, combined gel-coating and surface-film coating routes, for alkaline earth aluminates long after-glow phosphors was studied. The influence of the post-treatment on the microstructure and performances of the coated phosphors was investigated in details. The relations among the electric conductivity, the brightness and the pH values with the dip-ping time of coated phosphors in water were discussed. Results show that variation on the electric conductivity and pH value for the coated phosphors is insignificant, while a quick increase on the electric conductivity and pH value for the un-coated phosphors due to the decomposition. The luminescence brightness of coated phosphors, after 720 h dipped in water, remains 80% of its initial brightness, while the phosphors without post-treatment lose its luminescence property. Experiments show that for the coated phosphors, there is a continuous dense protecting layer on their surfaces, which makes the performance of the coated phosphors, minimized the influence by the circumstance, and even renovating the original crackles in the material particulars. These crackles are unfavorable to application. The coating treatment for phosphors makes these materials possess superior properties such as waterproof, heat-resistance and well dispersion and so they more suit to using in different fields.