title: Improvement of interfacial contacts for new small-molecule bulk-heterojunction organic photovoltaics.
abstract: The influence of protonation reactions between poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and a thiadiazolo[3,4-c]pyridine small-molecule donor are reported; these result in poor solar-cell performance due to a barrier for charge extraction. The use of a NiO(x)  contact eliminates such deleterious chemical interactions and results in substantial improvements in open-circuit voltage, fill factor, and an increased power conversion efficiency from 2.3% to 5.1%.
authors.affiliation: National Center for Photovoltaics, National Renewable Energy Laboratory, Golden, CO 80401, USA.
authors.forename: Andres
authors.initials: A
authors.lastname: Garcia
authors.forename: Gregory C
authors.initials: GC
authors.lastname: Welch
authors.forename: Erin L
authors.initials: EL
authors.lastname: Ratcliff
authors.forename: David S
authors.initials: DS
authors.lastname: Ginley
authors.forename: Guillermo C
authors.initials: GC
authors.lastname: Bazan
authors.forename: Dana C
authors.initials: DC
authors.lastname: Olson
mesh_terms: D002087:Butyrates / Q000737:chemistry; D011211:Electric Power Supplies; D004579:Electron Transport; D009930:Organic Chemicals / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry; D012993:Solar Energy
chemical_list: D002087:Butyrates; D009930:Organic Chemicals; D011725:Pyridines; C045572:ethyl butyrate