| 초록 |
To clarify the effect of a low-bandgap non-fullerene acceptor (NFA) on a power conversion efficiency (PCE) of ternary blend organic solar cells (OSCs), we investigated the excited-state dynamics in ternary blend systems composed of a donor-acceptor wide-bandgap polymer based on a benzodithiophene backbone (PBT-OTT), PC71BM, and ITIC using femtosecond transient absorption (fsTA) spectroscopy. We found the unique formation-pathway of ITIC-generated free carriers, which increases the PCE of ternary blend NFA OSCs more effectively than does the hole transfer from ITIC to PBT-OTT. Our findings of the charge-carrier dynamics in the ternary blend system may provide the important information that may lead to further increase in the PCE of OSCs. |
