The application of a magnetic field to improve polymer: Fullerence solar cell performance

Charge transport in a percolated network resulted from the mixing of donor (polymer) and acceptor materials is one of the important issues in improving the performance of polymer solar cells. We demonstrate a simple approach to enhance the performance of polymer solar cells based on poly(3-hexythiophene) (P3HT):fullerene blend incorporating a small amount of magnetic FePt-nanowires (FePt-NWs) as an additive. The photoactive film was prepared under the application of a magnetic field perpendicular to the substrate during solvent drying process. The power conversion efficiency has been improved up to ~ 60% for the treated cells. The improved device performance can be attributed to the overall improvement of polymer crystallinity.