两种以Znq2为基体的新型电致发光材料的合成与性能

以8-羟基喹啉为配体的金属配合物是一种性能优良的有机电致发光材料,其中有关8-羟基喹啉铝(Alq₃)研究已有大量报道,8-羟基喹啉锌(Znq₂)研究还有待发展。介绍了两种以Znq₂为基体的新型有机电致发光材料Znq₂(H₂O)₂和(Znq₂)₄的合成方法。用IR、XRD、TG、DTA和荧光测试方法进行表征与分析表明:Znq₂(H₂O)₂和(Znq₂)₄的玻璃化温度(T_g)分别为104.2℃和204.9℃;在161℃下Znq₂(H₂O)₂脱去水分子成为Znq₂,在361℃高温下四聚体(Znq₂)₄裂解为单体Znq₂;Znq₂(H₂O)₂和(Znq₂)₄具有很好的发光性能,在光致发光谱中λ_max分别是505,550nm。

Preparation and Characterization of Two Novel Znq2-based Electroluminescent Materials

Since Tang et al.developed a very high efficient fluorescent material(Alq₃) and made the first OELD in 1987,novel organic electroluminescent materials had attracted much interest.Though developed for ten years more,the performances of 8-hydroxyquinoline metal complexes were more excellent than other organic electroluminescent materials in commerce utilizations,such as good light performance,good thermal stability,and good film formability.Alq₃ was the best representation,research on performances and applications of Alq₃ has matured.But the research on Znq₂ was not enough,which limited the commerce utilizations as an excellent organic electroluminescent material.At this point,some foundation research works were done here.Two Znq₂-based organic electroluminescent materials,Znq₂(H₂O)₂ and(Znq₂)₄,were prepared and characterized by infrared absorption spectrum(IR),X-ray diffraction(XRD),thermogravimetry(TG),differential thermal analysis(DTA),photoluminescence(PL) spectrum and electroluminescence(EL) spectrum.It was shown that the deviating temperature of H₂O from Znq₂(H₂O)₂ is 161℃,the decomposing temperature of(Znq₂)₄ into Znq₂ is 361℃,the glass transition temperature of Znq₂(H₂O)₂ is 104.2℃ and that of(Znq₂)₄ is 204.9℃.In PL spectra,the peak wavelengths of Znq₂(H₂O)₂ and(Znq₂)₄ are 505 nm and 550 nm respectively.In EL spectra,the peak wavelength of (Znq₂)₄ is 539 nm.Because of special molecular spatial structure of(Znq₂)₄,there is an electron tunnel between adjacent(Znq₂)₄ molecules,which could increase electron transition efficiency from HOMO to LUMO and decrease drive voltage of OELD.The high glass transition temperature of(Znq₂)₄ could prolong the lifetime of OELD. Above all,(Znq₂)₄ have great potential in use as organic electroluminescent material.In addition,(Znq₂(H₂O)₂) has great light intensity and narrow FWHM in PL spectra,and it is also a kind of potential(excellent) organic electroluminescent material.Application of(Znq₂)₄ and Znq₂(H₂O)₂ in OELD will be discussed in detail in future articles.