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在一定量的激活剂PbO_2和助熔剂BaCl_2,BaSO_4存在下,通过碳酸钡和二氧化硅之间的固相反应制备光致发光材料二硅酸钡铅BaSi_2O_5:Pb~(2+)。为了使获得的产品是具有上述化学计量的化合物,以及具有最好的发光性能,我们用正交设计方法安排了一系列条件试验。试验结果指出,在合成二硅酸钡铅发光材料的反应中,反应温度和SiO_2/BaCO_3的摩尔比是最重要的因素。反应温度应高于1100℃,SiO_2/BaCO_3的摩尔比应在2.3—2.8之间。其它重要因素有:激活剂PbO_2加入量在0.04—0.17摩尔之间对产物发光强度均无明显影响,以0.08摩尔为最好。由于PbO_2在高温时分解及挥发,实际进入晶体的Pb~(2+)量仅为0.8％(摩尔百分)。助熔剂BaCl_2及BaSO_4的加入量分别以0.16摩尔及0.17摩尔为最好。灼烧时间以5小时为最好。 根据最佳条件所制备得到的BaSi_2O_5:Pb~(2+)发光材料在254nm激发下,它的发射光谱峰值为351.9nm,半高宽为39nm,它的发光强度为国内同类商品的111％,为日本东芝SPD_(-8)S的108％。用它制作紫外荧光灯管时,涂敷性能也较好。
The photoluminescence material BaSi 2 O 5: Pb 2+ was prepared by solid state reaction between barium carbonate and silica in the presence of a certain amount of activator PbO 2 and flux BaCl 2, BaSO 4. In order to obtain the product with the above stoichiometry and the best luminescence properties, we arranged a series of conditional tests using orthogonal design methods. The experimental results indicate that the reaction temperature and molar ratio of SiO 2 / BaCO 3 are the most important factors in the synthesis of barium lead disilicate luminescent materials. The reaction temperature should be higher than 1100 ℃, and the molar ratio of SiO_2 / BaCO_3 should be between 2.3 and 2.8. Other important factors are: activator PbO_2 in the amount of 0.04-0.17 mol between the product had no significant effect on the luminous intensity, the best 0.08 mol. Due to the decomposition and volatilization of PbO 2 at high temperature, the amount of Pb 2+ actually entering the crystal is only 0.8% (mol%). Flux BaCl_2 and BaSO_4 were added in amounts of 0.16 and 0.17 moles, respectively, the best. Burning time to 5 hours as the best. The emission peak of BaSi_2O_5: Pb ~ (2+) phosphor prepared under optimal conditions at 254 nm is 351.9 nm with a FWHM of 39 nm. Its emission intensity is 111% 108% of the Japanese Toshiba SPD _ (- 8) S. Use it to make UV fluorescent tubes, the coating performance is better.