Synthesis And Study On The Properties Of Organic Photovoltaic Materials Containing Thiazole And Indole Groups

Currently, the energy sources is a serious problem. Looking for a new type ofrenewable clean energy is the priority of scientific workers. organic solar cells (OSCs)have become a research hot spot in the field of scientific research and industry. Thebiggest problem is the photoelectric conversion efficiency that can not meet the needsof industrialization. Under this background, we designed and synthesized seven kindsof materials for oranic solar cells. The structures of the as-synthesized materials wereconfirmed by1H-NMR,13C-NMR, FT-IR and MALDI-TOF. The photophysical,electrochemical properties and photovoltaic performances of the materials have beeninvestigated. The main contents are as follows:1. Two new copolymers (PT-Tz-DTBT and PT-Tz-DTffBT) were synthesizedand developed for polymer solar cells. The photophysical, electrochemical andphotovoltaic properties of the copolymers were investigated. The two copolymersexhibited low HOMO energy levels，which were-5.58eV for PT-Tz-DTBT and-5.59eV for PT-Tz-DTffBT, respectively. When PC61BM was uesd as an electronacceptor and the two copolymers as electron donors, BHJ photovoltaic devicesexhibited the PCE of2.63%for PT-Tz-DTBT and3.75%for PT-Tz-DTffBT,respectively. And when PC71BM as an electron acceptor, a conventional and inverteddevice exhibited the promising PCE of3.65%and4.42%for PT-Tz-DTffBT.2. Two D-D-π-A organic dyes (SD1and SD2) were designed and synthesized forDSSCs. For the first time, a SCN group was introduced into a metal-free organic dyeSD2. The effects of the SCN group on the photophysical, and photovoltaic propertieswere investigated. It was found that the introduction of the SCN group to the SD2molecule leaded to a higher photovoltaic performance compared to SD1. SD2obtained a maximum PCE of6.74%, and for the SCN-free dyes SD1, the PCE was5.53%only.3. Three D-π-A organic dyes (LD1, LD2and LD3) were designed andsynthesized for dye-sensitised solar cells (DSSCs). The effects on their photovoltaicperformance from their different branched chain structure were mainly studied.Finally, it was found that the molecules which contain conjugated branched chainshave higher PCE values. The highest efficiency among the three molecules was basedon LD3, whose efficiency reached7.84%.