title: Graphene Anodes and Cathodes: Tuning the Work Function of Graphene by Nearly 2 eV with an Aqueous Intercalation Process.
abstract: To expand the applications of graphene in optoelectronics and microelectronics, simple and effective doping processes need to be developed. In this paper, we demonstrate an aqueous process that can simultaneously transfer chemical vapor deposition grown graphene from Cu to other substrates and produce stacked graphene/dopant intercalation films with tunable work functions, which differs significantly from conventional doping methods using vacuum evaporation or spin-coating processes. The work function of graphene layers can be tuned from 3.25 to 5.10 eV, which practically covers the wide range of the anode and cathode applications. Doped graphene films in intercalation structures also exhibit excellent transparency and low resistance. The polymer-based solar cells with either low work function graphene as cathodes or high work function graphene as anodes are demonstrated.
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Jan-Kai
authors.initials: JK
authors.lastname: Chang
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Wei-Hsiang
authors.initials: WH
authors.lastname: Lin
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Jieh-I
authors.initials: JI
authors.lastname: Taur
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Ting-Hao
authors.initials: TH
authors.lastname: Chen
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Guo-Kai
authors.initials: GK
authors.lastname: Liao
authors.affiliation: ‡National Synchrotron Radiation Research Center, Hsinchu 307, Taiwan (R.O.C.).
authors.forename: Tun-Wen
authors.initials: TW
authors.lastname: Pi
authors.affiliation: §Department of Optoelectronic Engineering, National Dong Hwa University, Hualien 974, Taiwan (R.O.C.).
authors.forename: Mei-Hsin
authors.initials: MH
authors.lastname: Chen
authors.affiliation: †Graduate Institute of Photonics and Optoelectronics and Department of Electrical Engineering, National Taiwan University, Taipei 106, Taiwan (R.O.C.).
authors.forename: Chih-I
authors.initials: CI
authors.lastname: Wu
keywords: doping; graphene; photoemission spectroscopy; polymer-free transfer; solar cell