Title Difenilamino ir di(4-metoksifenil)amino fragmentus turinčių elektroaktyvių fluorenono darinių sintezė ir savybių tyrima /
Translation of Title Synthesis and investigation of the properties of electroactive fluorenone derivatives containing diphenylamine or di(4-methoxyphenyl)amine moieties.
Authors Čalko, Viktorija
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Pages 56
Keywords [eng] optoelectronics ; organic semiconductor ; ionization potential ; charge-carrier mobility ; density functional theory.
Abstract [eng] Four new compounds with electron-donating diphenylamine and di(4-methoxyphenyl)amino moieties and electron-accepting 9-fluorenone and indene[1,2-b]fluorene fragments were synthesized. The structures of the compounds were confirmed by nuclear magnetic resonance spectroscopy and mass spectrometry. Thermogravimetric analysis showed that the compounds demonstrate high thermal stability, and their 5% mass loss temperature was detected in the range from 357 °C to 434 °C. Differential scanning calorimetry measurements revealed that fluorenone derivatives were isolated as crystalline materials and formed molecular glasses. Compounds containing a 9-fluorenone moiety were found to have lower 5% weight loss, melting, glass transition, and crystallization temperatures than analogous compounds with an indene [1,2-b] fluorene moiety. Cyclic voltammetry revealed that the synthesized compounds demonstrate reversible oxidation and reduction processes. The values of ionization potentials of the compounds (5.06–5.42 eV) estimated from the voltamperograms were similar to those values obtained by the electron photoemission method in air (5.20–5.41 eV). Fluorenone derivatives with methoxy groups were found to have lower ionization potential values because of the oxygen of methoxy groups donor properties. Xerographic time of flight method showed that the solid layers of compounds having di(4-methoxyphenyl)amino moieties demonstrate bipolar charge transfer - drift mobilities of electrons and holes were recorded in the layers. Measurements of the absorption spectra revealed that the fluorenone derivatives were characterized by reversible electron transfer.
Dissertation Institution Kauno technologijos universitetas.
Type Master thesis
Language Lithuanian
Publication date 2022