123rd General Meeting of the KCS

Type Poster Presentation
Area Polymer Chemistry
Room No. Exhibition Hall 2
Time 4월 19일 (금요일) 11:00~12:30
Code POLY.P-15
Subject Noncovalently Conformational Locking in Indacenodithiophene-based A-D-A type Molecule and Its Application to High-performing Non-fullerene Polymer Solar Cells
Authors Su Hong Park, Hyung Jong Kim, Cheol Hun Jeong, Nayeon Kwon, Ji Hye Lee, Min Ju Cho*, Dong Hoon Choi*
Department of Chemistry, Korea University, Korea
Abstract A new A-b-D-b-A-type n-type small molecule, IDT-3MT, was synthesized bearing a weak acceptor thiophene-3-carboxylate bridge (3MT = b) between indacenodithiophene as a donating core and 2-(3-oxo-2,3-dihydroinden-1-ylidene)-malononitrile as the accepting end groups. Compared to IDT-T bearing a neat thiophene bridge, IDT-3MT displayed a red-shifted absorption spectrum in the film state, which is a more effective complementary absorption behavior with PBDB-T as the donor material. Methyl-3-thiophenecarborxylate (3MT) moiety with weak electron affinity can lower the LUMO energy level to increase the difference of the LUMO energy levels between the donor and acceptor (ΔELUMO), and provide enhanced driving force for efficient exciton dissociation resulted as higher JSC in OSCs. Based on the results of grazing-incidence wide-angle X-ray scattering, the blend film of PBDB-T:IDT-3MT exhibited a more prominent face-on orientation and fine surface morphology compared with PBDB-T:IDT-T, which can facilitate charge transportation in the vertical direction. Among two acceptors, as-cast blend film (solvent additive free) of PBDB-T and IDT-3MT exhibited the highest power conversion efficiency of 8.40 % due to complementary absorption and favorable internal morphology in application of polymer solar cell.
E-mail parkshsd@korea.ac.kr