title: Solution-based electrical doping of semiconducting polymer films over a limited depth.
abstract: Solution-based electrical doping protocols may allow more versatility in the design of organic electronic devices; yet, controlling the diffusion of dopants in organic semiconductors and their stability has proven challenging. Here we present a solution-based approach for electrical p-doping of films of donor conjugated organic semiconductors and their blends with acceptors over a limited depth with a decay constant of 10-20 nm by post-process immersion into a polyoxometalate solution (phosphomolybdic acid, PMA) in nitromethane. PMA-doped films show increased electrical conductivity and work function, reduced solubility in the processing solvent, and improved photo-oxidative stability in air. This approach is applicable to a variety of organic semiconductors used in photovoltaics and field-effect transistors. PMA doping over a limited depth of bulk heterojunction polymeric films, in which amine-containing polymers were mixed in the solution used for film formation, enables single-layer organic photovoltaic devices, processed at room temperature, with power conversion efficiencies up to 5.9 ± 0.2% and stable performance on shelf-lifetime studies at 60 °C for at least 280 h.
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Vladimir A
authors.initials: VA
authors.lastname: Kolesov
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Canek
authors.initials: C
authors.lastname: Fuentes-Hernandez
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Chou
authors.affiliation: INAMORI Frontier Research Center, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan.
authors.forename: Naoya
authors.identifier: 0000-0003-4673-4512
authors.initials: N
authors.lastname: Aizawa
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Felipe A
authors.initials: FA
authors.lastname: Larrain
authors.affiliation: Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Applied Physics, Eindhoven University of Technology, Box 513, 5600 MB Eindhoven, Netherlands.
authors.forename: Alberto
authors.initials: A
authors.lastname: Perrotta
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Sangmoo
authors.initials: S
authors.lastname: Choi
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Samuel
authors.initials: S
authors.lastname: Graham
authors.affiliation: Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
authors.forename: Guillermo C
authors.initials: GC
authors.lastname: Bazan
authors.affiliation: Center for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA.
authors.forename: Thuc-Quyen
authors.initials: TQ
authors.lastname: Nguyen
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Seth R
authors.initials: SR
authors.lastname: Marder
authors.affiliation: Center for Organic Photonics and Electronics (COPE), School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
authors.forename: Bernard
authors.initials: B
authors.lastname: Kippelen