Synthesis and characterization of novel organic materials for application in organic light emitting diodes and dye sensitized solar cells

This thesis deals with synthesis and characterization of pi-Conjugated organic materials for using as emitters and dye molecules in optoelectronic devices. pi-Conjugated organic materials consist of a carbazole moiety as an electron donor, fluorine-oligothiophene moiety as a conjugated linker. A series of novel carbazole end-caped triphenylamine GnCT (n=1-4) were synthesized using Ullmann coupling reaction. Fluorescence spectra of the target molecules excited at max of each molecule show emission peak at blue region. The fluorescence quantum yields (F) of these fluorescence oligomers range from 0.37 to 0.12 and decrease as the steric in molecule increase. The maximum luminance of the organic light emitting diode device using G3CT as hole transporting layer was about 25,397 cd/m2 at an operating voltage of 10.8 V. Novel carbazole end-caped fluorine-benzothiadiazole GnBTF (n=1-4) were synthesized using Suzuki coupling reaction. Fluorescence spectra of the target molecules excited max of each molecule show emission peak at region. The fluorescence quantum yields (F) of these fluorescence oligomers range from 0.18 to 0.05 and decrease as the steric in molecule increase. Novel carbazole end-caped oligofluorene GnF3 (n=1-3) and GnF2 (n=1-3) were synthesized using Suzuki coupling reaction and Stille coupling, respectively. Fluorescence spectra of the target molecules excited at max of each molecule show emission peak at blue region. The fluorescence quantum yields (F) of GnF3 range from 0.96 to 0.91 and decrease as the steric in molecule increase.