| 초록 |
We designed a conjugated framework of small molecule donors with a symmetrical electron acceptor-donor-acceptor (A-D-A) type structure to induce the different open-circuit voltages (Voc) and light absorption range. A new series of conjugated small molecule donors, which is based on an electron-withdrawing (A) isoindigo (ID), were synthesized by conjugating with electron-rich (D) moieties, such as vinyl (V), benzene (B), thienothiophene (TT) and benzodithiophene (BDT). To understand the effects of these donors in non-fullerene polymer solar cells (PSCs), we systematically investigated the performances on their optical, electrical, and structural properties. As a result, the best power conversion efficiency (PCE) of 2.2%, recording high Voc (0.92V) value, was observed for the ID-BDT-ID:PNDIT-HD, due to its advantageous properties, including high light absorption coefficients, and properly aligned energy level with that of n-type polymer PNDIT-HD. |
