title: Improved photovoltaic performance of inverted polymer solar cells through a sol-gel processed Al-doped ZnO electron extraction layer.
abstract: We demonstrate that nanocrystalline Al-doped zinc oxide (n-AZO) thin film used as an electron-extraction layer can significantly enhance the performance of inverted polymer solar cells based on the bulk heterojunction of poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) and [6,6]-phenyl C(71)-butyric acid methyl ester (PC(70)BM). A synergistic study with both simulation and experiment on n-AZO was carried out to offer a rational guidance for the efficiency improvement. As a result, An n-AZO film with an average grain size of 13 to 22 nm was prepared by a sol-gel spin-coating method, and a minimum resistivity of 2.1 × 10(-3) Ω·cm was obtained for an Al-doping concentration of 5.83 at.%. When an n-AZO film with a 5.83 at.% Al concentration was inserted between the ITO electrode and the active layer (PCDTBT:PC(70)BM), the power conversion efficiency increased from 3.7 to 5.6%.
authors.forename: Jun Young
authors.initials: JY
authors.lastname: Kim
authors.forename: Eunae
authors.initials: E
authors.lastname: Cho
authors.forename: Jaehoon
authors.initials: J
authors.lastname: Kim
authors.forename: Hyeonwoo
authors.initials: H
authors.lastname: Shin
authors.forename: Jeongkyun
authors.initials: J
authors.lastname: Roh
authors.forename: Mariyappan
authors.initials: M
authors.lastname: Thambidurai
authors.forename: Chan-mo
authors.initials: CM
authors.lastname: Kang
authors.forename: Hyung-Jun
authors.initials: HJ
authors.lastname: Song
authors.forename: SeongMin
authors.initials: S
authors.lastname: Kim
authors.forename: Hyeok
authors.initials: H
authors.lastname: Kim
authors.forename: Changhee
authors.initials: C
authors.lastname: Lee