title: Graphene as transparent conducting electrodes in organic photovoltaics: studies in graphene morphology, hole transporting layers, and counter electrodes.
abstract: In this work, organic photovoltaics (OPV) with graphene electrodes are constructed where the effect of graphene morphology, hole transporting layers (HTL), and counter electrodes are presented. Instead of the conventional poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) PEDOT:PSS HTL, an alternative transition metal oxide HTL (molybdenum oxide (MoO(3))) is investigated to address the issue of surface immiscibility between graphene and PEDOT:PSS. Graphene films considered here are synthesized via low-pressure chemical vapor deposition (LPCVD) using a copper catalyst and experimental issues concerning the transfer of synthesized graphene onto the substrates of OPV are discussed. The morphology of the graphene electrode and HTL wettability on the graphene surface are shown to play important roles in the successful integration of graphene films into the OPV devices. The effect of various cathodes on the device performance is also studied. These factors (i.e., suitable HTL, graphene surface morphology and residues, and the choice of well-matching counter electrodes) will provide better understanding in utilizing graphene films as transparent conducting electrodes in future solar cell applications.
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors: Hyesung
authors: H
authors: Park
authors: Patrick R
authors: PR
authors: Brown
authors: Vladimir
authors: V
authors: Bulović
authors: Jing
authors: J
authors: Kong
mesh_terms: D011211:Electric Power Supplies; D004566:Electrodes; D004579:Electron Transport; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006108:Graphite / Q000737:chemistry*; D008027:Light; D049329:Nanostructures / Q000737:chemistry* / Q000528:radiation effects*; D009930:Organic Chemicals / Q000737:chemistry*; D010316:Particle Size; D012993:Solar Energy
chemical_list: D009930:Organic Chemicals; D006108:Graphite