Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye
Tezin Onay Tarihi: 2009
Öğrenci: ASLI TUBA TAŞKIN
Danışman: LEVENT KAMİL TOPPARE
Özet:A novel electroactive monomer 5,8-Di(1H-pyrrol-2-yl)-2, 3-di(thiophen-2-yl) quinoxaline (PTQ) was successfully synthesized via Stille Coupling reaction between quinoxaline and pyrrole. Nuclear magnetic resonance (1H NMR and 13C NMR) and Mass spectroscopy were used to characterize the monomer. The monomer was electrochemically polymerized in the presence of tetrabutylammonium perchlorate (TBAP) as supporting electrolyte in dichloromethane. Monomer reveals relatively low oxidation potential at +0.70V. Spectroelectrochemical behaviors and switching ability of homopolymer were investigated by UV-Vis spectroscopy and cyclic voltammetry. Two π-π* transitions were observed at 400 nm and 815 nm with a low band gap, 1.0 eV. Polymer possesses 66% optical contrast in the Near IR region, which may be promising in NIR electrochromic device applications. Spectroelectrochemical behaviors and switching ability of copolymers were investigated by UV-Vis spectroscopy and cyclic voltammetry. Copolymers of PTQ in the presence of BiEDOT and BEBT were synthesized via potentiodynamic method in DCM/TBAP (0.1 M) solvent-electrolyte couple. P(PTQ-co-BiEDOT) reveals oxidation potential at +0.45V, whereas P(PTQ-co-BEBT) reveals oxidation potential at +0.70V. The spectroelectrochemical behavior of the P(PTQ-co-BiEDOT) and P(PTQ-co-BEBT) in comparison to homopolymer revealed solid evidence of copolymerization based upon the differences in the spectral signatures. Switching time of the polymers was evaluated by kinetic studies upon measuring the percent transmittance (%T) at the maximum contrast point.