Electroluminescence and photovoltaic properties of light-emitting devices and solar cells comprising 2-pyran-4-ylidene-malononitrile conjugated polymers

Several main-chain type and triazine-branched, fluorene and thiophene copolymers containing a 2-pyran-4-ylidene-malononitrile derivative were synthesized using the Suzuki coupling reaction. A triazine-branched fluorene-based device displayed superior electroluminescence performance with a brightness ≤1031 cd m−2 and an efficiency of 1.97 cd A−1. A polymer solar cell, comprising an interpenetrating network of conjugated polymer as electron donor and a fullerene derivative, (6,6)-phenyl-C61-butyric acid methyl ester, as the electron acceptor, exhibited photocurrent density and photo-energy conversion efficiency of 5.07 mA cm−2 and 0.50%, respectively.