Perylene diimide–thienylenevinylene-based small molecule and polymer acceptors for solution-processed fullerene-free organic solar cells

•Small molecule 3 and polymer 5 based on perylene diimide and thienylenevinylene were synthesized.•Compounds 3 and 5 were used as acceptors to fabricate fullerene-free polymer solar cells.•Polymer solar cells based on 5 exhibited higher efficiencies (1.00%) than those of 3 (0.69%).

A small molecule and a polymer based on perylene diimide and thienylenevinylene were designed and synthesized. Both small molecule and polymer exhibited excellent thermal stability with decomposition temperatures of >400 °C and strong absorption in the visible region (300–800 nm). These two compounds showed highest occupied molecular orbital levels of −5.57 and −5.70 eV and lowest unoccupied molecular orbital levels of −3.72 and −3.67 eV, respectively. Solution processed fullerene-free polymer solar cells based on the small molecule acceptor and the polymer acceptor afforded power conversion efficiencies of up to 0.69% and 1.00%, respectively. Comparative studies of the absorption, energy levels, charge transport, morphology and photovoltaic properties of the small molecule and polymer were carried out.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide