Exploration of the structure-property relationship of push-pull based dyads for single-molecule organic solar cells

The synthesis, characterization and use of three donor-σ-acceptor molecular dyads as organic photoactive layer are reported herein. Based on push-pull π-conjugated systems, the donor moiety is connected through a non-conjugated σ-linker to a PC61BM derived block. Three different π-connectors, constituting the push-pull unit, namely a bithiophene (BT), a thienothiophene (TT) and a cyclopentadithiophene (CPDT) units were selected to assess the impact of the chemical bridging (CPDT) or fusing (TT) on the electronic, electrochemical and therefore photovoltaic properties. Hence through a better understanding of the structure-property relationships, power conversion efficiencies exceeding the symbolic percent have been reached in single-molecule organic solar cells.