Electrochromism with selenophene derivatives


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Kimya Bölümü, Türkiye

Tezin Onay Tarihi: 2008

Öğrenci: KADİR AYDEMİR

Danışman: LEVENT KAMİL TOPPARE

Özet:

A novel selenophene-based monomer; 1,4-di(selenophen-2-yl) benzene (DSB), synthesized via Stille coupling reaction of 1,4 dibromobenzene and tributyl (2-selenophenyl) stannane and corresponding conducting homopolymer (Poly (DSB)) was electrochemically synthesized in the presence of tetrabutylammoniumhexafluorophosphate (TBAPF6) as the supporting electrolyte in dichloromethane. The resulting conducting polymer was characterized by Cyclic Voltammetry (CV), Fourier Transform Infra Red Spectrometry (FTIR) and UltravioletVisible Spectrometry (UV-Vis Spectrometry). Spectroelectrochemistry analysis and kinetic studies of Poly (DSB) revealed * transition ( max) at 340 nm with almost zero percent transmittance ( T%) concurrently with striking and rapid (0.6 s) absorbance change at near infrared region (1250 nm) with 35% percent transmittance, indicating that Poly (DSB) is a very suitable near infrared electrochromic material. Copolymer of selenophene with ethylenedioxythiophene (EDOT) was potentiostatically synthesized. Poly (selenophene-co-EDOT) was characterized by Cyclic Voltammetry, FTIR and UV-Vis Spectrometry. During spectroelectrochemistry studies, * transition ( max) was observed at 555 nm with a switching time of 1.4 s and 39% transmittance. Polaron and bipolaron bands were observed at 851 nm and 1299 nm, respectively. Switching time at 1299 nm was 1.8 s with a percent transmittance of 72. Copolymer of DSB with EDOT (Poly (DSB-co-EDOT)) was synthesized and characterized. max, polaron and bipolaron bands were observed at 457 nm, 696 nm and 1251 nm, respectively. A rapid switching time (0.2 s) with 12% transmittance was observed at 696 nm. At the near infrared region (1251 nm), satisfactory percent transmittance (35%) and a moderate switching time (1.75 s) were observed.