Fullerene–non-fullerene hybrid acceptors for enhanced light absorption and electrical properties in organic solar cells. (June 2021) - Wu, Z.
Abstract: Two fullerene–non-fullerene hybrid acceptors, IDTIC-PC61 BM (IP) and PC61 BM-IDTIC-PC61 BM (PIP), are synthesized by combining a non-fullerene acceptor, 3, 9-bis(2-methylene-(3-(1, 1-dicyanomethylene)-indanone))-5, 5, 11, 11-tetrakis(4-hexylphenyl)-dithieno[2, 3-d:2′, 3′-d']-s-indaceno[1, 2-b:5, 6-b']dithiophene (IDTIC), and a fullerene derivative, phenyl-C61 -butyric acid methyl ester (PC61 BM). To evaluate the potential of these hybrid acceptors, we fabricate organic solar cells (OSCs) based on the four different acceptors (i.e. IP, PIP, IDTIC, and PC61 BM) and the same polymer donor (PBDB-T). In IP and PIP, the IDTIC moiety compensates for the poor light absorption of PC61 BM in the visible wavelength region, improving the short-circuit current density ( J SC ) of the hybrid acceptor-based OSCs (11.9 → 13.1 mA cm −2 ). Meanwhile, the charge transport and recombination properties of the PBDB-T:IDTIC devices improve significantly after the substitution of IDTIC with IP or PIP, leading to a significant increase in the fill factor (0.54 → 0.68) as well as J SC (11.8 → 13.1 mA cm −2 ) of the devices. Therefore, owing to the synergistic effect of the broad light absorption of IDTIC and efficient electron transport of PC61 BM, the hybrid acceptor-based OSCs show significantly higher power conversion efficiencies of 8.81% (PBDB-T:PIP) and 8.17% (PBDB-T:IP) than the PBDB-T:PC61 BM (7.62%) and PBDB-T:IDTIC (5.98%) OSCs. The results demonstrate the effectiveness of the hybrid acceptor design in overcoming the shortcomings of individual acceptors and improving their photovoltaic performance. Graphical abstract: Image 1 Highlights: Development of new fullerene–non-fullerene hybrid acceptors for efficient organic solar cells. Synergistic effects of broad light absorption and good electron transport ability of hybrid acceptor approaches. Systematic investigation of hybrid acceptors compared with the reference fullerene and non-fullerene acceptors.