par Zhang, Xinran;Richter, Lee J;DeLongchamp, Dean M;Joseph Kline, R;Hammond, Matthew R;Mc Culloch, Ian;Heeney, Martin;Ashraf, Raja S;Smith, Jeremy N;Anthopoulos, Thomas D;Schroeder, Bob;Geerts, Yves 
;Fischer, Daniel A;Toney, Michael F
Référence Journal of the American Chemical Society, 133, page (15073)
Publication Publié, 2011
;Fischer, Daniel A;Toney, Michael FRéférence Journal of the American Chemical Society, 133, page (15073)
Publication Publié, 2011
Article révisé par les pairs
| Résumé : | We describe a series of highly soluble diketo pyrrolo-pyrrole (DPP)-bithiophene copolymers exhibiting field effect hole mobilities up to 0.74 cm 2 V -1 s -1, with a common synthetic motif of bulky 2-octyldodecyl side groups on the conjugated backbone. Spectroscopy, diffraction, and microscopy measurements reveal a transition in molecular packing behavior from a preferentially edge-on orientation of the conjugated plane to a preferentially face-on orientation as the attachment density of the side chains increases. Thermal annealing generally reduces both the face-on population and the misoriented edge-on domains. The highest hole mobilities of this series were obtained from edge-on molecular packing and in-plane liquid-crystalline texture, but films with a bimodal orientation distribution and no discernible in-plane texture exhibited surprisingly comparable mobilities. The high hole mobility may therefore arise from the molecular packing feature common to the entire polymer series: backbones that are strictly oriented parallel to the substrate plane and coplanar with other backbones in the same layer. © 2011 American Chemical Society. |
