Nanostructure dependence of field-effect mobility in regioregular poly(3-hexylthiophene) thin film field effect transistors.
Low polydispersity regioregular polythiophenes with number average molecular weights ranging from 2 to 13 kDa were cast under the same conditions from solution to form a series of field effect transistors (FETs). Tapping mode AFM and grazing incidence small-angle X-ray scattering revealed that in all cases the polymers formed regular nanofibrillar morphologies with the width of nanofibrils proportional to the weight average contour length of polymer chains, indicating that conjugated backbones were oriented perpendicular to the nanofibril axes. FET charge carrier mobilities exhibited exponential dependence on nanofibril width, pointing to the decisive role of extended conjugated pathways in charge transport.
Department of Chemistry, Carnegie Mellon University, 4400 Fifth Avenue, Pittsburgh, Pennsylvania 15213, USA.
Rui
R
Zhang
Bo
B
Li
Mihaela C
MC
Iovu
Malika
M
Jeffries-El
Geneviève
G
Sauvé
Jessica
J
Cooper
Shijun
S
Jia
Stephanie
S
Tristram-Nagle
Detlef M
DM
Smilgies
David N
DN
Lambeth
Richard D
RD
McCullough
Tomasz
T
Kowalewski
D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D012666:Semiconductors; D013876:Thiophenes / Q000737:chemistry*
D013876:Thiophenes; C507295:poly(3-hexylthiophene)