Indacenodithiophene-based conjugated polymers incorporating alkylthiophene side chains: Improvement of organic solar cell performance

摘要: Abstract Varying the structures of conjugated side chains can be an efficient approach toward tailoring optoelectronic properties polymers. In this study, we synthesized four indacenodithiophene (IDT)-based chain donor–acceptor alternating We introduced different acceptor units (difluorobenzothiadizole: PIDTHT-FBT ; difluoroquinoxaline: PIDTHT-QF dicyanoquinoxaline: PIDTHT-QCN diketopyrrolopyrrole: PIDTHT-DPP ) to study effects on (absorption spectra, energy levels, hole mobility) polymers and their resulting organic photovoltaic (OPV) devices. The levels highest occupied molecular orbitals for new were deeper when they featured alkylthiophene chains. Films these materials blended with PC 71 BM exhibited sufficiently high space-charge-limited current (SCLC) mobilities (>1.2 × 10 −5  cm 2  V −1 s charge carrier extraction. greatest OPV performance was that device incorporating , a power conversion efficiency 5.15% under illumination AM 1.5G solar light (1000 W m −2 ). Thus, (two-dimensional) IDT optimized groups are prospective applications.