SrAl_2B_2O_7:Dy^(3+)材料的制备及其发光性能

Preparation and luminescence characteristics of SrAl_2 B_2 O_7 :Dy^(3+) phosphor

采用高温固相法制备了SrAl2B2O7:Dy3+发光材料.在350nm紫外光激发下,测得SrAl2B2O7:Dy3+材料的发射光谱为一个多峰宽谱,主峰分别为480,573和678nm;分别和Dy3+的4F9/2→6H15/2,4F9/2→6H13/2,4F9/2→6H11/2的跃迁发射相对应;监测573nm的发射峰,得到材料的激发光谱为一个多峰宽谱,主峰分别为295,325,350,365,400nm.研究了Dy3+掺杂浓度对SrAl2B2O7:Dy3+材料发射光谱的影响,随着Dy3+掺杂浓度的增大,SrAl2B2O7:Dy3+材料的Iy/Ib逐渐增大,根据Judd-Ofelt理论解释了其原因.随着Dy3+掺杂浓度的增大,Dy3+的4F9/2→6H13/2跃迁产生的573nm发射峰强度先增大,在4%时达到最大值,之后减小,其自身的浓度猝灭机理为电偶极-电偶极相互作用.不同的电荷补偿剂Li+,Na+,K+的引入均使发光强度得到提高,尤其以Li+最佳,发光强度提高了大约33%.

The SrAl2B2O7： Dy3 ＋ phosphor is synthesizd through a general high temperature solid-state reaction, and its luminescence properties are investigated. The emission spectrum of SrAl2B2O7：Dy3 ＋ shows the bands at 480nm,573nm and 678nm under the 365nm excitation,corresponding to the 4F9/2 →6H15/2,4F9/2 →6H13/2 and 4F9/2 →6H11/2 typical transitions of Dy3 ＋ respectively. The excitation spectrum for 573nm emission has excitation bands at 295 nm,325 nm,350 nm,365 nm and 400nm. The influence of doped Dy3 ＋ contentration on the emission spectrum and the luminescent intensity of SrAl2B2O7：Dy3 ＋ is investigated. The result shows that the intensity ratio of yellow emission （573nm） to blue emission （483 nm）,Iy /Ib,increases with the increase of Dy3 ＋ concentration,which may be explained by the Judd-Ofelt theory. The luminescent intensity increases first with the increase of Dy3 ＋ concentration, then decreases. The concentration self-quenching is attributed to the d-d interaction according to the Dexter theory. The introducing of charge compensation agents of Li ＋ ,Na ＋ and K ＋ ions can augment the emission intensity. It is found that Li ＋ ions are the best to enhance the emission intensity.