摘要
为了考察杂质阴离子对Eu2 + 光谱的影响 ,应用光谱方法研究了复合氟化物中氧离子对氟离子的取代与Eu2 + 光谱变化的关系 结果表明 :在KCaF3和BaY2 F8基质中 ,氧的存在产生了Eu2 + 新的发光中心 ,其中一种为正常的Eu2 + 的发射中心 ,即Eu2 + (F- )中心 ,另一种为氧离子对氟离子取代形成的发射中心 ,即Eu2 + (O2 - )中心 ;对于KCaF3基质 ,随还原气氛中H2 含量的增加 ,Eu2 + (O2 - )发射中心强度逐渐降低 ;对于BaY2 F8基质 ,随还原气氛中H2 含量的增加 ,Eu2 + (O2 - )发射中心的激发和发射能量向高能方向移动 由于氧在氟化物基质中结合的牢固 ,即使在完全H2气氛中还原 ,Eu2 + (O2 - )
Spectrograph study was carried out to investigate the influence of O 2- ion as impurity anion on the change of spectra of Eu 2+ by substitution of O 2- ion for F - ion in KCaF 3 and BaY 2F 8. The results showed that there existed two kinds of luminescent centers of Eu 2+ , including Eu 2+ (F -) center, a normal emission center of Eu 2+ in the these hosts, and Eu 2+ (O 2- ) center, formed by substitution of O 2- ion for F - ion. For KCaF 3, emission intensity of Eu 2+ (O 2- ) center became weak sharply by high temperature reaction with H 2 as a reduction atmosphere. For BaY 2F 8, the excitation and emission wavelength of Eu 2+ (O 2- ) center was shifted to high energy with the increase of the content of H 2 in reduction atmosphere. These were very different from Lattourrett's results. Owing to the strength of Eu-O bonding in fluorides, once Eu 2+ (O 2- ) center was formed , it was impossible to eliminate it entirely. This was different from the case of complex oxides with Eu 2+ (F -) new luminescent center due to the replacement of O 2- ion by F - ion , Eu 2+ (F -) center being capable of removal by high temperature reaction in air.[
出处
《暨南大学学报（自然科学与医学版）》
CAS
CSCD
2000年第3期81-84,共4页
Journal of Jinan University(Natural Science & Medicine Edition)
