| 초록 |
Organic Solar Cells are being spotlighted as eco-friendly energy sources. To commercialize them, the high photoconversion efficiency (PCE) is needed. Key factors that determine it are Voc (open-circuit voltage), Jsc (Short-circuit current), and FF(Fill Factor). In particular, the longer conjugation length is beneficial to JSC values, so we introduced a thienothiophene group to increase the conjugation length. We synthesized four polymers, so-called t-HD, tt-HD, t-OD, and tt-OD (‘t’ means thiophene, ‘tt’ means thienothiophene, ‘HD’ means 2-hexyldecyl, and ‘OD’ means 2-octyldodecyl). Four polymers were synthesized by Stille-coupling polymerization using anhydrous toluene and N,N'-dimethylformamide (10:1 v/v). To investigate photovoltaic performances, we fabricated an inverted arrangement with [ITO/ZnO/active layer/MoO3/Ag], and that were measured using AM 1.5G solar simulator (100 mW/cm2). The maximum PCE was 5.21% for tt-HD due to high Jsc and FF values. |
