title: Nanoimprinting-induced nanomorphological transition in polymer solar cells: enhanced electrical and optical performance.
abstract: We have investigated the effects of a directly nanopatterned active layer on the electrical and optical properties of inverted polymer solar cells (i-PSCs). The capillary force in confined molds plays a critical role in polymer crystallization and phase separation of the film. The nanoimprinting process induced improved crystallization and multidimensional chain alignment of polymers for more effective charge transfer and a fine phase-separation between polymers and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) to favor exciton dissociation and increase the generation rate of charge transfer excitons. Consequently, the power conversion efficiency with a periodic nanostructure was enhanced from 7.40% to 8.50% and 7.17% to 9.15% in PTB7 and PTB7-Th based i-PSCs, respectively.
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Seonju
authors: S
authors: Jeong
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Changsoon
authors: C
authors: Cho
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Hyunbum
authors: H
authors: Kang
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Ki-Hyun
authors: KH
authors: Kim
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Youngji
authors: Y
authors: Yuk
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Jeong Young
authors: JY
authors: Park
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Bumjoon J
authors: BJ
authors: Kim
authors: †Graduate School of Energy, Environment, Water, and Sustainability (EEWS), ‡Graphene Research Center, §Department of Chemical and Biomolecular Engineering, and ∥Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Korea Advanced Institute Science and Technology (KAIST), Daejeon 305-701, Republic of Korea.
authors: Jung-Yong
authors: JY
authors: Lee
keywords: inverted polymer solar cell; nanoimprinting; nanomorphology; periodic nanostructure; phase segregation