ZnS型发光材料光老化的研究

INVESTIGATION FOR PHOTOAGEING OF ZnS TYPE PHOSPHORS

用X射线衍射谱证实了ZnS光致发光材料经紫外线照射后,体色逐渐变灰至黑是由于ZnS离解析出Zn所引起并发现尚有其它组分存在.还研究了不同波长的紫外线照射和材料粒经大小对ZnS发光材料光老化的影响得出一些新的实验结果.

Under UV radiation, the body colour of ZnS type photoluminescent phosphor changes from gray to dark,at the same time the brightness of phosphor decreases (pho-toageing). As well known, light deterioration mechanism has been clarified, that is, under UV radiation, zinc atom which comes from the dissociation of ZnS,results in the brightness decay and the change of material colour. In this paper,the above conclusion has been identified by X-ray diffraction patterns measurement and analysis of ZnS phosphors. It is also found, that non-zinc element impurity phase is presented in X-ray diffraction patterm. The effects of different wavelength UV radiation on light deterioration of phosphors are studied in this paper. It is shown that the photoageing of phosphors is caused by 185nm UV. The effect of particle size on photoageing is also examined, it is concluded, that the smaller the particle size, the more serious the photoageing.