The phase behavior of a polymer-fullerene bulk heterojunction system that contains bimolecular crystals (pages 499–503)
Nichole Cates Miller, Roman Gysel, Chad E. Miller, Eric Verploegen, Zach Beiley, Martin Heeney, Iain McCulloch, Zhenan Bao, Michael F. Toney and Michael D. McGehee
Article first published online: 24 FEB 2011 | DOI: 10.1002/polb.22214
Some polymer:fullerene blends used in bulk heterojunction solar cells, such as pBTTT blends with PC71BM, form bimolecular crystals due to fullerene intercalation between the polymer side chains. By using differential scanning calorimetry and 2D grazing incidence X-ray scattering with in-situ thermal annealing the pBTTT:PC71BM phase diagram is determined. In addition, it's also shown to be possible to suppress intercalation by heating the blends above the eutectic temperature.