title: Formation of nanopatterned polymer blends in photovoltaic devices.
abstract: In this paper, we demonstrate a double nanoimprinting process that allows the formation of nanostructured polymer heterojunctions of composition and morphology that can be selected independently. We fabricated photovoltaic (PV) devices with extremely high densities (10(14)/mm(2)) of interpenetrating nanoscale columnar features in the active polymer blend layer. The smallest feature sizes are as small as 25 nm on a 50 nm pitch, which results in a spacing of heterojunctions at or below the exciton diffusion length. Photovoltaic devices based on double-imprinted poly((9,9-dioctylfluorene)-2,7-diyl-alt-[4,7-bis(3-hexylthien-5-yl)-2,1,3-benzothiadiazole]-2',2''-diyl) (F8TBT)/ poly(3-hexylthiophene) (P3HT) films are among the best polymer-polymer blend devices reported to date with a power conversion efficiency (PCE, eta(e)) of 1.9%.
authors.affiliation: The Nanoscience Centre, University of Cambridge, Cambridge, United Kingdom.
authors.forename: Ximin
authors.initials: X
authors.lastname: He
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Guoli
authors.initials: G
authors.lastname: Tu
authors.forename: David
authors.initials: D
authors.lastname: Hasko
authors.forename: Sven
authors.initials: S
authors.lastname: Hüttner
authors.forename: Ullrich
authors.initials: U
authors.lastname: Steiner
authors.forename: Neil C
authors.initials: NC
authors.lastname: Greenham
authors.forename: Richard H
authors.initials: RH
authors.lastname: Friend
authors.forename: Wilhelm T S
authors.initials: WT
authors.lastname: Huck
mesh_terms: D052160:Benzothiazoles / Q000737:chemistry*; D011211:Electric Power Supplies; D004563:Electrochemistry; D049329:Nanostructures / Q000737:chemistry*; D036103:Nanotechnology / Q000295:instrumentation / Q000379:methods*; D010316:Particle Size; D010777:Photochemistry; D011108:Polymers / Q000737:chemistry*; D013499:Surface Properties; D013876:Thiophenes / Q000737:chemistry*
chemical_list: D052160:Benzothiazoles; D011108:Polymers; D013876:Thiophenes; C550774:poly((9,9-dioctylfluorene)-2,7-diyl-alt-(4,7-bis(3-hexylthien-5-yl)-2,1,3-benzothiadiazole)-2',2''-diyl); C507295:poly(3-hexylthiophene)