title: Tunable charge transport using supramolecular self-assembly of nanostructured crystalline block copolymers.
abstract: Electronically functionalized block copolymers, combining covalently linked p-type and n-type blocks, show switching behavior of charge transport in organic field effect transistors (OFETs). The electronically active subunits self-assemble into continuous microdomains in a nanoscale regime, thereby forming percolation channels for holes or electrons or both depending on the composition and processing conditions. Here, we establish a charge transport-morphology relation for donor-acceptor block copolymers with two crystalline blocks. The n-type and p-type blocks self-assemble into two-dimensional lattices of π-π stacks and main chain polymer lamellae, respectively, over a broad composition range. Controlling the crystallization preferences of the two blocks by thermal annealing allows controlling the OFET polarity. Depending on the block ratio, the charge transport can be tuned from p-type to n-type or p-type to ambipolar, respectively. The impact of nanostructured phase separation is further delineated by X-ray diffraction, time-resolved spectroscopy, and scanning electron microscopy studies.
authors.affiliation: Cavendish Laboratory, University of Cambridge, United Kingdom.
authors.forename: Sven
authors.initials: S
authors.lastname: Huettner
authors.forename: Michael
authors.initials: M
authors.lastname: Sommer
authors.forename: Justin
authors.initials: J
authors.lastname: Hodgkiss
authors.forename: Peter
authors.initials: P
authors.lastname: Kohn
authors.forename: Thomas
authors.initials: T
authors.lastname: Thurn-Albrecht
authors.forename: Richard H
authors.initials: RH
authors.lastname: Friend
authors.forename: Ullrich
authors.initials: U
authors.lastname: Steiner
authors.forename: Mukundan
authors.initials: M
authors.lastname: Thelakkat
mesh_terms: D004579:Electron Transport; D004867:Equipment Design; D019544:Equipment Failure Analysis; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties; D014173:Transistors, Electronic
chemical_list: D046911:Macromolecular Substances; D011108:Polymers