Advancing Integration of Direct C–H Arylation-Derived Star-Shaped Oligomers as Second Acceptors for Ternary Organic Solar Cells

Abstract

Organic solar cells (OSCs) could benefit from the ternary bulk heterojunction (BHJ), a method that allows for fine-tuning of light capture, cascade energy levels, and film shape, in order to increase their power conversion efficiency (PCE). In this work, the third components of PM6:Y6 and PM6:BTP-eC9 BHJs are a set of four star-shaped unfused ring electron acceptors (SSUFREAs), i.e., BD-IC, BFD-IC, BD-2FIC, and BFD-2FIC, that are facilely synthesized by direct C−H arylation. The four SSUFREAs all show complete complementary absorption with PM6, Y6, and BTP-eC9, which facilitates light harvesting and exciton collection. When BFD-2FIC is added as a third component, the PCEs of PM6:Y6 and PM6:BTP-eC9 binary BHJs are able to be improved from 15.31% to 16.85%, and from 16.23% to 17.23%, respectively, showing that BFD-2FIC is useful for most effective ternary OSCs in general, and increasing short circuit current (J SC ) and better film morphology are two additional benefits. The ternary PM6:Y6:BFD-2FIC exhibits a 9.7% percentage of increase in PCE compared to the PM6:Y6 binary BHJ, which is one of the highest percentage increases among the reported ternary BHJs, showing the huge potential of BFD-2FIC for ternary BHJ OSCs.

Accessing Poly(DA-ran-Dπ) Ternary Copolymers via Direct C–H Arylation for Ultrahigh Photocatalytic Hydrogen Production

“…In recent years, the boron- and tin-free DArP (i.e., the straightforward C–H/C–Br coupling) has emerged as a green and atom-economical alternative to the traditional Suzuki and Stille C–M/C–Br (M = B and Sn) couplings. − Here, the Pd-catalyzed DArP ,, (Scheme ) among DBTSO 2 , EDOT, and 1,4-dibromobenzene (DBB) led to the formation of five target LCPs EDBz-0 , EDBz-25 , EDBz-50 , EDBz-75 , and EBz-100 , wherein 0, 25, 50, 75, and 100 represent the percentages of phenyl units involved. By varying the feed ratios of DBB, the ternary LCPs incorporating different contents of the phenyl π-spacer and DBTSO 2 were facilely obtained (Scheme ).…”