Summary: | 碩士 === 國立臺灣科技大學 === 材料科學與工程系 === 105 === Two novel monomer, 3,8-bis(5-bromo-4-(2-octyldodecyl)thiophen-2-yl)tetraazapyrene (12), 3,8-bis(5-bromo-4-(2-octyldodecyl)thiophen-2-yl)benzo[c]cinnoline (14) were prepared via several synthetic steps from 2,6-dinitroanline、1,4-dibromo-2-nitrobenzene. Novel conjugated polymer TAPTVT and BZCTVT were prepared from (E)-1,2-bis(5-(trimethylstannyl)thiophen-2-yl)ethene (16) and monomer (12) and (14) by using Stille coupling polymerization in microwave reactor. The structures of TAPTVT and BZCTVT were characterized by 1H-NMR and elemental analysis. The number molecular weight of TAPTVT and BZCTVT, measured in THF were 38.3 and 51.1 KDa, respectively. The decomposition temperature at 5 % weight loss (T d5 %) of TAPTVT and BZCTVT were 410 and 406 ℃, respectively, exhibiting outstanding thermal stabilities of TAPTVT and BZCTVT. The optical and electrochemical properties of TAPTVT and BZCTVT were investigated by UV-vis spectroscopy and cyclic voltammetry. For TAPTVT and BZCTVT, absorption peaks at 574 and 522 nm were observed. The cyclic voltammertric studies revealed that TAPTVT and BZCTVT exhibited low LUMO (-3.61 and -3.49 eV) and HOMO (-5.64 and -5.63 eV) energy levels. A bottom-gate, top-contact OFET based on TAPTVT and BZCTVT exhibited p-channel behavior with hole mobilities of 4.63 × 10-4 and 1.04 × 10-4 cm2 V-1 S-1 and on/off ratio greater than 104 after thermal annealing. Grazing incidence X-ray diffraction result suggest that thin film of TAPTVT and BZCTVT were prefered edge-on orientation and exhibited better crystallinity after thermal annealing. TAPTVT and BZCTVT based OFET exhibited p-channel semiconducting properties. To the best of our knowledge, it is the first tetraazapyrene moieties based OFET.
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