Pérez-Gutiérrez Enrique, Calvo Franciso D, Beristain Miriam F, Venkatesan Perumal, Thamotharan Subbiah, Percino M Judith
Unidad de Polímeros y Electrónica Orgánica, Instituto de Ciencias, Benemérita Universidad Autónoma de Puebla, Val3-Ecocampus Valsequillo, Independencia O2 Sur 50, San Pedro Zacachimalpa, Puebla, Mexico.
Decanatura de Ingenierías, Universidad Popular Autónoma de Puebla, 21 Sur #1103, Barrio de Santiago, Puebla, C.P, 72410, Mexico.
J Fluoresc. 2024 Aug 13. doi: 10.1007/s10895-024-03880-w.
The analysis of the shift in photoluminescence emission for a blend of polyvinylcarbazole and acrylonitrile derivative compounds is reported. The small-molecule compounds have different functional groups, phenyl, pyridine, or methyl phenyl, attached to an acrylonitrile group. According to the functional group, the blue emission for pure dye shifts to green or yellowish in the blend film. Several PVK:dye ratios from 0:100 to 20:80 were used for film deposition. The film morphology was analyzed by atomic force microscopy; for low dye content, homogeneous films were achieved. However, aggregates of several micrometers are formed on the surface of films with higher dye concentrations. The shift in emission occurs only with PVK, and for a non-conjugated matrix such as polystyrene, the emission remains unchanged. The interaction of dyes with PVK leading to change in emission was also achieved by grinding dye and polymer. Results showed that shifts in emission could come from exciplex formation along with changes in dye intermolecular interactions. The blend films were highly transparent in the visible spectra due to the absorption in the UV region for dye and matrix. The films with ratio PVK: dye ratio 80:20 was used as active layer in OLEDs.
报道了对聚乙烯咔唑与丙烯腈衍生物化合物共混物的光致发光发射位移的分析。小分子化合物具有连接到丙烯腈基团上的不同官能团，即苯基、吡啶基或甲基苯基。根据官能团的不同，纯染料的蓝色发射在共混膜中会移向绿色或淡黄色。使用了从0:100到20:80的几种聚乙烯咔唑与染料的比例来进行薄膜沉积。通过原子力显微镜对薄膜形态进行了分析；对于低染料含量，获得了均匀的薄膜。然而，在染料浓度较高的薄膜表面形成了几微米大小的聚集体。发射位移仅在聚乙烯咔唑存在时发生，而对于诸如聚苯乙烯这样的非共轭基质，发射保持不变。通过研磨染料和聚合物也实现了染料与聚乙烯咔唑的相互作用导致发射变化。结果表明，发射位移可能来自激基复合物的形成以及染料分子间相互作用的变化。由于染料和基质在紫外区域的吸收，共混膜在可见光谱中具有高透明度。聚乙烯咔唑与染料比例为80:20的薄膜被用作有机发光二极管的活性层。
