title: Fabrication of free-standing multilayered graphene and poly(3,4-ethylenedioxythiophene) composite films with enhanced conductive and mechanical properties.
abstract: Poly(3,4-ethylenedioxythiophene) (PEDOT)-based film has relatively high conductivity, flexibility, and transmittance. However, the improvement for mechanical strength and conductivity is still required to be adopted for commercial applications. Graphene, a one atom thick planar sheet of sp(2)-bonded carbon atoms, is considered as an ideal nanocomposite material for these purposes. In this study, we have developed PEDOT and graphene composite films, two-layered graphene/PEDOT and three-layered graphene/PEDOT/graphene, by using a spin-coating method. The conductivity of a 32 nm thick PEDOT film was improved more than twice by graphene deposition, while the high transmittance of the composite film was maintained over 90%. The mechanical strength of the PEDOT and graphene composite film shows 6-fold enhancement over the pristine PEDOT film. Because of the contribution of graphene layer for enhancing the mechanical strength, a 44 nm thick graphene/PEDOT/graphene could be obtained as a free-standing film by delaminating the graphene layer from the glass substrate under a weak base solution. These results imply that the graphene not only improves the conductivity and mechanical strength of PEDOT but also enables to produce a free-standing film which could find a variety of applications in the fields of organic electronic, sensors, and optoelectronics.
authors.affiliation: Department of Chemical and Biomolecular Engineering (BK21 program) and Institute for the BioCentury, KAIST, 335 Gwahangno, Yuseong-gu, Daejeon 305-701, Korea.
authors.forename: Ki Seok
authors.initials: KS
authors.lastname: Choi
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Jong Seob
authors.initials: JS
authors.lastname: Choi
authors.forename: Tae Seok
authors.initials: TS
authors.lastname: Seo
mesh_terms: D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D004553:Electric Conductivity; D019563:Mechanics; D008567:Membranes, Artificial; D053761:Nanocomposites / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D011108:Polymers / Q000737:chemistry*
chemical_list: D019086:Bridged Bicyclo Compounds, Heterocyclic; D008567:Membranes, Artificial; D011108:Polymers; C121383:poly(3,4-ethylene dioxythiophene); D002244:Carbon