Synthesis of Bioinspired Curcuminoid Small Molecules for Solution-Processed Organic Solar Cells with High Open-Circuit Voltage

Borondifluoride complexes of curcuminoid derivatives end-capped with triphenylamine groups were designed for solution-processed bulk-heterojunction organic solar cells. They were obtained very simply in a one-pot synthesis from cheap building blocks. Compared to push–pull systems based on borondifluoride complexes of hydroxychalcones, curcuminoids present the donor–acceptor–donor electronic structure and exhibit significantly improved chemical and thermal stability and photovoltaic performance. Indeed, power conversion efficiency up to 4.14% and high open-circuit voltage over 1.0 V have been achieved using PC 61 BM as acceptor.