合成了一种新型的具有压致荧光变色效应的聚集诱导增强发光(PAIE)化合物二咔唑四苯乙烯;通过核磁共振、质谱和元素分析等手段对其进行了结构表征;利用紫外吸收光谱、荧光发射光谱、热分析和X射线衍射等手段研究了化合物的基本性能.实验结果表明,随着水含量的增加,该化合物溶液荧光强度增强了171倍,荧光量子产率提高了100倍,表现出明显的聚集诱导增强发光效应;在外界因素作用下该化合物固体样品可实现结晶态与无定形态的相互转变.结晶态的荧光发射波长为450 nm,无定形态为480 nm,相差30 nm,说明该化合物具有明显的压致荧光变色效应;将该化合物用于制备发光器件,未经优化的器件亮度达2438 cd/m2,电流效率为2.87 cd/A,流明效率为1.81 lm/W.该化合物是一种多功能材料.
The development of organic fluorescent materials was of great interest for both fundamental research and practical applications.Piezofluorochromic or piezochromic fluorescent material was a "smart" material of which fluorescent properties were changed in response to external pressure stimuli.However,piezofluorochromic materials depended on the change of physical molecular packing modes were remaining extremely rare.In this work,a new discarbazolyl tetraphenylethylene compound was synthesized.The chemical structures of the derivative was determined by 1H NMR,MS and elemental analyses,and its properties were investigated by PL,TGA,DSC and CV methods.The results show that the compound possess piezofluorochromic properties as well as aggregation-induced emission enhancement effect.The PL intensity and quantum yield in DMF/H2O with high water fraction were about 171,100 times higher than those in pure DMF,respectively.The piezofluorochromic nature was generated through phase transformation from crystalline state(450 nm) to amorphous state(480 nm) under the external stimuli.The organic light emitting diode(OLED) device fabricated with the compound as non-doped emitters exhibited good performances with a maximum brightness of 2438 cd/m2,a maximum current efficiency of 2.87 cd/A,and a maximum power efficiency of 1.81 lm/W.It is indicated that the compound is a multi-functional luminophor.