Synthesis and characterization of D-A-A type regular terpolymers with narrowed band-gap and their application in high performance polymer solar cells

Novel D-A-A type regular terpolymers of PBDT-DTQ and PIDT-DTQ were designed and synthesized. In contrast to the common D-A alternating copolymers, PBDT-DTQ and PIDT-DTQ exhibited a much broader absorption with the narrowed band-gap of 1.54 and 1.63 eV. Meanwhile, in contrast to PBDT-DTQ, a deeper HOMO energy level and also a higher charge carrier mobility was obtained for PIDT-DTQ. Therefore, a superior PCE value of 6.41% with an enhanced Jsc of 11.42 mA/cm2 and Voc of 0.86 V was achieved for PIDT-DTQ-based solar cells.303