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Eu~(2+)激活的硅酸钡镁(BaMg_2Si_2O_7:Eu~(2+))荧光粉通过再烧结或再洗涤,其特性获得明显改善。当该粉加 NH_4F 助熔剂重新烧结并用 KOH 重新洗过后,其特性改善最大。该粉用于荧光灯,100小时灯的维持率较高,光输出是原来荧光粉的两倍,用低能电子谱法(ESCA)分析该粉的表面特性,发现其表面化学性质发生了惊人的变化。也发现,荧光粉表面组分与灯的特性之间,具有密切的关系。Eu~(2+)激活硅酸钡镁为 Sylvania 的217型荧光粉,最早由 Barry 于1970年研制。该粉一般常用于复印灯。用254nm 激发产生398nm 发射,峰值半宽度为24nm。用 Barry 法制备该粉,一般100小时后灯的性能很差:只有50％维持,紫外输出3000mW。该粉通过重新烧结或重新洗涤处理后,其光通与维持率均有明显改善,零小时的光输出提高20％。100小时的改善更明显,光输出达到原来的2倍。为了认识这一改进的机理,用低能电子谱法研究粉的表面,用 x 射线衍射谱法(XRD)和原子吸收光谱学(AA)来研究荧光粉体的结构。分析的结果表明,再处理对粉体化学性质影响很小,然而荧光粉表面成分却发生了惊人的变化。发现表面成分与灯性能之间密切相关。水文指出了ESCA 在 Eu~(2+)激活 BaMg_2Si_2O_7荧光粉研究中的贡献。讨论了再处理对荧光粉表面化学性质的影响以及表面性质与灯性能之间的关系。
The Eu 2+ activated BaMg 2 Si 2 O 7: Eu 2+ phosphor has been significantly improved by re-sintering or re-washing. When the powder plus NH_4F flux re-sintering and re-washed with KOH, its greatest improvement in properties. The powder used in fluorescent lamps, 100-hour lamp high maintenance, light output is twice the original phosphor, low energy electron spectroscopy (ESCA) analysis of the surface properties of the powder and found that the surface chemical properties of the amazing changes have taken place . It is also found that there is a close relationship between the phosphor component and the lamp characteristics. Eu ~ (2 +) activated barium magnesium silicate is Sylvania’s 217 phosphor, first developed by Barry in 1970. The powder is commonly used for copying lights. Excitation with 254 nm yields a 398 nm emission with a peak half-width of 24 nm. The Barry method to prepare the powder, the lamp performance is generally poor after 100 hours: only 50% to maintain the UV output 3000mW. The powder through the re-sintering or re-washing treatment, its lumen and maintenance rates have significantly improved, zero hour light output increased by 20%. The 100-hour improvement is even more pronounced, with the light output reaching twice the original. In order to understand the mechanism of this improvement, the surface of the powder was studied by low energy electron spectroscopy, and the structure of the phosphor was studied by X-ray diffraction (XRD) and atomic absorption spectroscopy (AA). The results show that the reprocessing has little effect on the chemical properties of the powders, however, the surface composition of the phosphors has undergone astonishing changes. It was found that there is a close correlation between surface composition and lamp performance. Hydrology has pointed out the contribution of ESCA in Eu2 + -activated BaMg2Si2O7 phosphors. The effect of reprocessing on the phosphor surface chemistry and the relationship between surface properties and lamp performance are discussed.