Synthesis and characterization of single and double alkoxybenzothiadiazole-based nonfullerene acceptors for organic solar cells
발표자
()
초록
내용
Three alkoxybenzothiadiazole (BTO)-based nonfullerene acceptors were synthesized with a central core unit with a single BTO (A') or double BTO (A'-p-A') structure. In the double BTO core molecules, thiophene (T) or thienothiophene (TT) p-linkers were introduced to explore the effects of these structural modifications on the optical and electrochemical properties. Tuning of the central core with a single BTO or double BTO structure changed the absorption properties, HOMO/LUMO levels, and molecular crystallinity. The photovoltaic performance of devices based on these acceptors varied considerably, with the BTO-FIC, BTO-T-FIC and BTO-TT-FIC devices displaying power conversion efficiencies (PCEs) of 10.6%, 5.4% and 6.5%, respectively. The superior PCE of the BTO-FIC device is attributed to the enhanced hole and electron mobilities, minimized carrier recombination, and high crystallinity of the BTI-FIC blend film, which contribute to the enhancement of the JSC and PCE.