title: Diketopyrrolopyrrole (DPP)-Based Donor-Acceptor Polymers for Selective Dispersion of Large-Diameter Semiconducting Carbon Nanotubes.
abstract: Low-bandgap diketopyrrolopyrrole (DPP)-based polymers are used for the selective dispersion of semiconducting single-walled carbon nanotubes (s-SWCNTs). Through rational molecular design to tune the polymer-SWCNT interactions, highly selective dispersions of s-SWCNTs with diameters mainly around 1.5 nm are achieved. The influences of the polymer alkyl side-chain substitution (i.e., branched vs linear side chains) on the dispersing yield and selectivity of s-SWCNTs are investigated. Introducing linear alkyl side chains allows increased polymer-SWCNT interactions through close π-π stacking and improved C-H-π interactions. This work demonstrates that polymer side-chain engineering is an effective method to modulate the polymer-SWCNT interactions and thereby affecting both critical parameters in dispersing yield and selectivity. Using these sorted s-SWCNTs, high-performance SWCNT network thin-film transistors are fabricated. The solution-deposited s-SWCNT transistors yield simultaneously high mobilities of 41.2 cm(2) V(-1) s(-1) and high on/off ratios of greater than 10(4) . In summary, low-bandgap DPP donor-acceptor polymers are a promising class of polymers for selective dispersion of large-diameter s-SWCNTs.
authors.affiliation: Department of Chemical Engineering, Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Ting
authors.initials: T
authors.lastname: Lei
authors.affiliation: Department of Chemical Engineering, Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.|Graduate Institute of Electronics Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China.
authors.forename: Ying-Chih
authors.initials: YC
authors.lastname: Lai
authors.affiliation: Department of Chemistry, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Guosong
authors.initials: G
authors.lastname: Hong
authors.affiliation: Department of Chemical Engineering, Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Huiliang
authors.initials: H
authors.lastname: Wang
authors.affiliation: BASF Schweiz AG, GVE/B, Schwarzwaldallee 215, 4002, Basel, Switzerland.
authors.forename: Pascal
authors.initials: P
authors.lastname: Hayoz
authors.affiliation: BASF SE, GVE/F, Carl-Bosch-Strasse 38, 67056, Ludwigshafen, Germany.
authors.forename: R Thomas
authors.initials: RT
authors.lastname: Weitz
authors.affiliation: Department of Chemistry, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Changxin
authors.initials: C
authors.lastname: Chen
authors.affiliation: Department of Chemistry, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Dai
authors.affiliation: Department of Chemical Engineering, Department of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA.
authors.forename: Zhenan
authors.initials: Z
authors.lastname: Bao
keywords: carbon nanotubes; conjugated polymers; field-effect transistors; selective dispersion; side-chain effects