| The research progress of the conjugated polymers especially the ones containing thiophene and devices for organic solar cells, organic field-effect transistors and mercury detection were summarized systematically in this dissertation. The dissertation is focusing on the synthesis of conjugated polymers with broad absorption and high hole mobility. The absorption spectra, hole mobility and the voltage of open-circuit play important part in the power conversion efficiency of the polymer solar cells. Several kinds of intermediates and conjugated polymers were designed and synthesized, and characterized by FTIR, 1H NMR, 13C NMR, GC-MS, elemental analysis. The photophysical and electrochemical properties were studied by UV-vis absorption spectra, photoluminescense spectra and cyclic voltammograms. We also investigated the PCE of the solar cells and field-effect transistor properties based on as-synthesized copolymers. In addition, two D-π-A alternative copolymers, P(TPA-TPZ) and P(Ph-TPZ) with thieno[3,4b]pyrazine in the backbone, were synthesized by Wittig-Horner polycondensation and applied in mecury detection. The main research were listed as follows:1. In order to improve the hole mobility, a novel conjugated polymer DOTPAV-PT with triphenylamine unit in the side chain was synthesized and characterized in details, and the photophysical and electrical properties were investigated . According to the experimental results, DOTPAV-PT possessed a broad absorption and a relative higher mobility of 1.25×10-4 cm2V-1s-1, which authorized that the incorporation of triphenylamine can improve the hole mobility of the polymer.2. In order to improve the hole mobility further, a novel conjugated polymer CARV-PT with carbazol-vinylene (CARV) in the side chain was synthesized and characterized in details and investigated. The experimental results show that the polymer possessed a broad absorption and a higher mobility of 5.2×10-4 cm2V-1s-1, which indentifed the use of the carbazol-vinylene on the improvement of hole mobility. Polymer solar cell with CARV-PT as the donor and PCBM as acceptor(1:1wt) was fabricated, and the power conversion efficiency of the device , was 0.20%, under the illumination of AM 1.5,100 mW/cm2 .3. In order to improve the hole mobility of PT and lower the HOMO and broaden the absorption spectrum, a novel conjugated polymer, poly(thienylene-vinylene-thienylene) with cyano substituent (CN-PTVT) was synthesized. CN-PTVT possessed a broad absorption ranging from 400 to 750 nm investgated by UV-vis spectra. The polymer has a relative narrower bandgap with its HOMO and LUMO ?5.15 eV and ?3.22 eV respectively, which indicated that the incorporation of cyano- remarkably lowered the HOMO level of the polymer. The polymer solar cell based on CN-PTVT as donor and PCBM as acceptor showed a relatively high open-circuit voltage of 0.82 V and a power conversion efficiency of 0.3% under the illumination of AM 1.5, 100 mW/cm2. The FET based on CN-PTVT shows a high hole mobility of 5.9×10?3 cm2 V?1 s?1 and a high Ion/Ioff ratio of 4.9×104, which is near the highest performance among the air-stable amorphous polymers.4. Two alternative copolymers of thieno[3,4b]pyrazine (TPZ) and triphenylamine (TPA) or phenylene (Ph), P(TPA-TPZ) and P(Ph-TPZ), were synthesized by Wittig-Horner polycondensation. Both of them in different solvents show strong solvatochromism phenomenon, and P(TPA-TPZ) in CHCl3 is red and green in HCOOH, while P(Ph-TPZ) in CHCl3 is yellow and purple-red in HCOOH. The fluorescence of the copolymer solutions is efficiently quenched upon the addition of Hg2+. Thus The remarkable PL quenching can be used for detecting mercury ion. Both of the polymers show high selectivity and sensitivity towards Hg2+.
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