Optical Transmittance Enhancement of Flexible Copper Film Electrodes with a Wetting Layer for Organic Solar Cells
- Authors
- Zhao, Guoqing; Song, Myungkwan; Chung, Hee-Suk; Kim, Soo Min; Lee, Sang-Geul; Bae, Jong-Seong; Bae, Tae-Sung; Kim, Donghwan; Lee, Gun-Hwan; Han, Seung Zeon; Lee, Hae-Seok; Choi, Eun-Ae; Yun, Jungheum
- Issue Date
- 8-11월-2017
- Publisher
- AMER CHEMICAL SOC
- Keywords
- flexible transparent electrode; organic solar cell; copper; ultrathin film; wetting layer
- Citation
- ACS APPLIED MATERIALS & INTERFACES, v.9, no.44, pp.38695 - 38705
- Indexed
- SCIE
SCOPUS
- Journal Title
- ACS APPLIED MATERIALS & INTERFACES
- Volume
- 9
- Number
- 44
- Start Page
- 38695
- End Page
- 38705
- URI
- https://scholar.korea.ac.kr/handle/2021.sw.korea/81570
- DOI
- 10.1021/acsami.7b10234
- ISSN
- 1944-8244
- Abstract
- The development of highly efficient flexible transparent electrodes (FTEs) supported on polymer substrates is of great importance to the realization of portable and bendable photovoltaic devices. Highly conductive, low-cost Cu has attracted attention as a promising alternative for replacing expensive indium tin oxide (ITO) and Ag. However, highly efficient, Cu-based FTEs are currently unavailable because of the absence of an efficient means of attaining an atomically thin, completely continuous Cu film that simultaneously exhibits enhanced optical transmittance and electrical conductivity. Here, strong two-dimensional (2D) epitaxy of Cu on ZnO is reported by applying an atomically thin (around 1 nm) oxygen-doped Cu wetting layer. Analyses of transmission electron microscopy images and X-ray diffraction patterns, combined with first-principles density functional theory calculations, reveal that the reduction in the surface and interface free energies of the wetting layers with a trace amount (1-2 atom %) of oxygen are largely responsible for the two-dimensional epitaxial growth of the Cu on ZnO. The ultrathin 2D Cu layer, embedded between ZnO films, exhibits a highly desirable optical transmittance of over 85% in a wavelength range of 400-800 nm and a sheet resistance of 11 Omega sq(-1). The validity of this innovative approach is verified with a Cu-based FTE that contributes to the light-to-electron conversion efficiency of a flexible organic solar cell that incorporates the transparent electrode (7.7%), which far surpasses that of a solar cell with conventional ITO (6.4%).
- Files in This Item
- There are no files associated with this item.
- Appears in
Collections - College of Engineering > Department of Materials Science and Engineering > 1. Journal Articles
- Graduate School of Energy and Environment (KU-KIST GREEN SCHOOL) > Department of Energy and Environment > 1. Journal Articles
Items in ScholarWorks are protected by copyright, with all rights reserved, unless otherwise indicated.