Polymerized A-DA'D-A type small-molecule acceptors for high performance all-polymer solar cells: progress and perspective

A-DA’D-A type polymerized small-molecule acceptors(PSMAs) have very recently received wide attention because they possess advantages such as synthetic flexibility, narrowed bandgap, low energy loss, and impressive mechanical properties. With efforts on design and synthesis of PSMAs and polymer donors, significant progress has been made on all polymer solar cells(allPSCs) with power conversion efficiencies exceeding 18%. In this review, we focus on structure-property-performance relationships of the A-DA’D-A type PSMAs. First, we in-depth review the regio-random, regio-regular, and random ternary series by focusing on their structural modification such as from aspects of side-chains, halogenation, selenophene-containing and linkers, respectively. Second, we review the mechanically flexible and stretchable properties, which helps to find structural gene that correlates the mechanical properties. Third, we review the impressive small energy loss. In all, this review provides structural and material’s clues, helpfully for designing high-performance all-PSCs.