合成了一种新型的有机电致发光材料水杨醛缩乙二胺锌[Zn(salen)],并对其结构与性能进行了表征。Zn(salen)具有较高的热稳定性,利用真空热蒸镀的方法很容易制备高质量、无定型薄膜。Zn(salen)的HOMO、LUMO能级及电化学带隙分别为-5.87,-3.41,2.46eV。在365nm紫外光的照射下,Zn(salen)粉体具有强的蓝光发射,但其薄膜具有黄光发射。在正向电压的驱动下,器件ITO/CuPc/NPD/Zn(salen)/Al的EL发光峰位于552nm,是色坐标为x=0.504,y=0.316的黄光发射,器件的启动电压7.5V,最大亮度301cd/m^2,电流效率1.6cd/A。无论是Zn(salen)薄膜的光致发光还是器件的电致发光,与Zn(salen)粉体相比,都发生了很大的红移现象,这归因于薄膜中Zn(salen)聚集态的形成。
A new EL material, [ N, N'-bis (salicylidene) -ethylenediamine ] zinc [ Zn (salen) ] was synthesized and characterized. Zn(salen) exhibits high thermal stability, excellent thin film forming ability. Its HOMO, LUMO and electrochemical band gap were estimated to be -5.87 eV, -3.41 eV, and 2.46 eV by cyclic voltammetry, respectively. Zn(salen) powder exhibits bright blue emitting, but Zn(salen) film exhibits yellow emitting under radiation of 365nm. The device ITO/CuPc/NPD/Zn( salen)/Al could emit yellow light. The EL peak was at about 552 nm with CIE coordinates of x = 0.504, y = 0.316. The device has a turn-on voltage of about 7.5 V and a maximum brightness of about 301 cd/m^2. The current efficiency is about 1.6 cd/A.