共掺Mo^(6+)离子的Ca_4LaNbW_4O_(20)∶Eu^(3+)荧光粉的发光特性

Photoluminescence Characteristics of Red-emitting Phosphors Ca_4 LaNbW_4O_20∶Eu^(3+) Incorporated with Mo^(6+) Ions

采用高温固相法制备了红色荧光粉Ca4LaNb(W1-x Mo x)4O20∶Eu3+并研究了样品的发光性质。Ca4LaNbW4O20∶Eu3+的激发光谱中包含一个宽的激发带,峰值位于275 nm,归属于WO2-4基团的电荷迁移跃迁。随着Mo6+离子的掺入,Ca4LaNbW4O20∶Eu3+位于275 nm处的吸收带变宽,其原因是O2--Eu3+的电荷迁移跃迁增强。在Ca4LaNb(W1-x Mo x)4O20∶Eu3+的发射光谱中,400~500 nm间较宽的发射带属于WO2-4基团的发射带,而位于591 nm和616 nm的尖锐的发射峰分别属于Eu3+的5D0→7F1磁偶极跃迁和5D0→7F2电偶极跃迁发射。随着Mo6+离子浓度的增加,WO2-4基团的发射带强度下降,从而提高了色纯度。

Red-emitting phosphors Ca 4 LaNb(W 1-x Mo x) 4 O 20 ∶ Eu3 +were synthesized by the solidstate reaction,and the photoluminescence properties of these compounds were investigated.The excitation spectra of Ca 4 LaNbW 4 O 20 ∶ Eu3 +show a broad excitation band centered at 275 nm,which attribute to the charge transfer(CT) transition of WO2 4 complex.With the introduction of Mo6 +ions into Ca 4 LaNbW 4 O 20 ∶ Eu3 +,the absorption band at 275 nm broadens due to the enhancement of CT transitions of O2--Eu3 +.The emission spectra of Ca 4 LaNb(W 1-x Mo x) 4 O 20 ∶ Eu3 +exhibit sharp emission peaks at 591 and 616 nm of Eu3 +transitions and a 400 ~ 500 nm broad emission band of WO2 4 transition.With the increase of Mo6 +content,the intensity of broad emission band of WO2 4 transition decreases.The pure red color is obtained.