铕离子掺杂碱土金属铝硼硅荧光玻璃的制备与发光性能

Preparation and Luminescent Properties of Europium-doped Alkaline Earth Aluminum Borosilicate Fluorescent Glass

采用熔融冷却法在空气条件下制备了含不同碱土金属氧化物的铕离子掺杂铝硼硅酸盐玻璃Al2O3–B2O3–Si O2–Eu2O3–MO（M=Mg,Ca,Sr,Ba）,考察了玻璃的密度、摩尔体积、光学碱度等物理性质,分析了玻璃的结构和发光性能。结果表明：从含Mg到含Ba玻璃,摩尔体积逐渐上升,玻璃化转变温度（Tg）依次下降。在381 nm波长激发下,所有玻璃在469 nm处均存在Eu2＋的5d→4f跃迁发射,在615 nm处存在Eu3＋的5D0→7F2跃迁发射,表明玻璃在空气中实现了Eu3＋→Eu2＋的部分还原,其中在含Sr玻璃中,Eu3＋还原程度相对最大,Eu2＋发光最强。所有玻璃均为非晶态,结构中存在的[BO4]、[Al O4]、[Si O4]四面体网络结构,有利于屏蔽Eu2＋不被氧化。从含Mg到含Ba玻璃,四面体网络Q4结构单元中桥氧键断裂程度上升,形成更多的Q3、Q2结构单元,使玻璃结构对称性、致密性下降。在近紫外光激发下,玻璃发光色坐标均位于白光区域内,表明该系列铕离子掺杂铝硼硅玻璃在白光LED上存在潜在应用。

Europium ion doped alkaline earth metal oxide aluminum borosilicate glasses（Al2O3–B2O3–Si O2–MO（M=Mg,Ca,Sr,Ba）were prepared in air by a rapid melt quenching technique.The physical properties of glasses（i.e.,density,molar volume as well as optical basicity）were investigated,and the structure and luminescence properties of glasses were also analyzed.The results show that the molar volume of glasses from Mg-glass to Ba-glass increases gradually and glass transition temperature（Tg）decreases progressively,thus reducing the compactness of the glass structure.A broad peak centered at 469 nm and a sharp peak at 615 nm emits simultaneously under 381 nm light excitation.The two peak are correspond to the 5d→4f transition of Eu2＋and 5D0→7F2 of Eu3＋,respectively,which manifests that partly reduction of Eu3＋to Eu2＋occurs in air.Also,the Eu2＋emission intensity and the reductive degree of Eu3＋reach a maximum in the Sr-glass.All the glasses are amorphous.The network structures of[BO4],[Al O4],[Si O4]in the glasses,which are helpful to shielding Eu2＋to be oxidized.The more Q3 and Q2 units increase gradually from Mg-glass to Ba-glass when the partially bridge oxygen originates from tetrahedral network structure of Q4 to be broken,thus decreasing the symmetry and compactness of glass structure.The color coordinates of the glasses are also located in the white light region under the excitation of near-UV light,indicating that europium ion doped alkaline earth metal aluminum borosilicate glasses have a promising potential application in white LED.