Synthesis Of Oligothiophene Derivatives Organic Photovoltaic Materials Andapplication Research

Oligothiophenes and derivatives with well-defined structures have attracted a great of attention recently not only as model compounds for electrically conducting polythiophenes but also as a new class of organicπ-electron system. In order to study novel performance and exploit applied value in more fields of oligothiophenes and derivatives, a series of oligothiophenes and derivatives: 2,3′:4′,2″-terthiophene(I3T), 5,5″-dicyano-2,3′:4′,2″-terthiop- hene(I3T-2CN), 5,5″-dicyano-2,2′:5′,2″-terthiophene(3T-2CN), 2,2′:5′,2″:5″, 2″′:5″′,2″″-quin- quethiophene(5T), 2,3,4,5-tetrathiopenyl-thiophene(XT) , 2,5(5′-cyano-thiopenyl)-3,4-terthio- penyl-thiophene(XT-2CN) were designed and synthesized. Their molecular structures were charactered by MS, 1HNMR, IR, HPLC.Photophysical and electrochemical properties of the compounds were measured by UV-Vis absorption spectra, fluorescence spectra and cyclic voltammetry.In the system of organic salt /organic solvent, the electrochromic properties of I3T and XT-2CN were studied. The final results showed the reversible color changes of the electrochemical doped films of I3T and XT-2CN were separately from white to blue and yellow to yellowish green. The final results suggested they had great potential as a new type of electrochromic material.The photovoltaic performances of I3T-2CN, 3T-2CN, XT-2CN, XT and 5T were investigated by the heterojunction organic photovoltaic devices. The power conversion efficiency of photovoltaic cells of ITO-glass/I3T-2CN/PTCDA/Al, ITO-glass/3T-2CN/PTCD- A/Al, ITO-glass/XT-2CN/PTCDA/Al, ITO-glass/XT/PTCDA/Al, and ITO-glass/5T/PTCDA/ Al were separately 0.19%, 2.24%, 0.65%, 0.58% and 2.49%.