Intercalated vs Nonintercalated Morphologies in Donor-Acceptor Bulk Heterojunction Solar Cells: PBTTT:Fullerene Charge Generation and Recombination Revisited. - Collado-Fregoso, E; Hood, SN; Shoaee, S; Schroeder, BC; McCulloch, I; Kassal, I; Neher, D; Durrant, JR (Journal of Physical Chemistry Letters, 2017)