| 초록 |
Polymer solar cell efficiency are determined by various factors. At this time, Voc is one of the important factors in determining efficiency. To make deep HOMO energy level, many study are used electron withdrawing group. In this study, fluoro withdrawing group and cyano functional group were compared. The polymers,(PB-T-DCNPz, PB-T-DFPz) were synthesized by stile coupling reaction. All polymer dissolved in chloroform and chlorobenzene at high temperature. thermal stability of these polymer was measured by Thermo gravimetric analysis (TGA). At 5% weight loss, these polymer showed over 330℃. PB-T-DFPz and PB-T-DCNPz showed maximum absorption spectra at 508 nm and 580 nm, respectively.In film state, maximum peak 711nm and 802nm. The HOMO value of each substance measured by CV is -5.25eV for PB-T-DFPz and -5.51eV for PB-T-DCNPz.The HOMO of PB-T-DCNPz was 0.26 eV lower. However, due to the high Jsc of PB-T-DFPz, PB-T-DCNPz showed 2.02% PCE, lower than PB-T-DFPz 4.14% PCE. |
