Synthesis of Soluble Triazole Molecule for Application in Solution-processable Organic Light-emitting Devices

• Main Authors: Cheng, Chien-Wei, 鄭建威
• Other Authors: Yang, Sheng-Hsiung
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/82594482407261603665

碩士 === 國立交通大學 === 光電科技學程 === 102 === The goal of this research is to synthesize soluble triazole derivative (BEHP-TAZ), to study its optical, electrochemical, and thermal properties, and to evaluate the performance of this material in triple-layer light-emitting devices. The principle of molecular design is introducing branched alkoxy chains on both ends to improve solubility of the material, and incorporating benzene ring to separate triazole center core from chain ends. The conjugation length is also elongated. The result from differential scanning calorimetry reveals that its glass transition tempeature is at 84 oC. The maximum UV-visible absorption and fluorescence emission wavelengths of the material in film state are located at 310 and 399 nm, respectively. The results obtained from cyclic voltammetric analysis and absorption spectrum show that the highest-occupied molecular orbital, lowest-unoccupied molecular orbital, and bandgap of the material are -5.86, -2.64, and 3.22 eV, respectively. Finaly, triple-layer light-emitting devices with configuration of ITO/PEDOT/Polymer/BEHP-TAZ/Al were fabricated and compared with double-layer devices, where soluble triazole molecule BEHP-TAZ was used as electron transporting layer, MEH-PPV or PFO as emissive layer. The experimental result demonstrates that the incorporation of soluble triazole molecule BEHP-TAZ brings significant enhanchent in brightness and efficiency of the devices, indicating its potential application in light-emitting devices.