Optimization, characterization and upscaling of aqueous solar nanoparticle inks for organic photovoltaics using low-cost donor: acceptor blend

We present the optimization and upscaling of water-based nanoparticle inks based on a novel donor-acceptor pair consisting of poly(3-hexylthiophene) (P3HT) and a newly developed indene-C-60 multiadducts (ICxA) that is comprised of indene-C-60 monoadduct (ICMA), indene-C-60 bisadduct (ICBA), and indene-C-60 trisadduct (ICTA). This material system has been used as a case study to explore the transition from OPV materials optimised for small-scale spin-coating to those optimised for large-scale printing. In particular, we have explored the effects of transitioning from a small-scale BHJ ink formulated from a high-cost acceptor to a large-scale NP ink formulated from a low-cost fullerene mixture. We show that it is possible to use a low-cost acceptor and to formulate the inks at scale with no loss in device performance.