Title: Cobalt Oxide (CoOx) as an Efficient Hole-Extracting Layer for High Performance Inverted Planar Perovskite Solar Cells
Authors: Shalan, Ahmed Esmail
Oshikiri, Tomoya
Narra, Sudhakar
Elshanawany, Mahmoud M.
Ueno, Kosei
Wu, Hui-Ping
Nakamura, Keisuke
Shi, Xu
Diau, Eric Wei-Guang
Misawa, Hiroaki
Department of Applied Chemistry
Institute of Molecular science
Keywords: cobalt oxide;hole-extraction layer;perovskite solar cell;photoluminescence;photovoltaic devices
Issue Date: 14-Dec-2016
Abstract: CoOx is a promising hole-extracting layer (HEL) for inverted planar perovskite solar cells with device configuration ITO/CoOx/CH3NH3PbI3/PCBM/Ag. The devices fabricated according to a simple solution procedure showed the best photovoltaic performance attaining power conversion efficiency (PCE) of 14.5% under AM 1.5 G 1 sun irradiation, which is significantly superior to those of materials fabricated with a traditional HEL such as PEDOT:PSS (12.2%), NiOx (10.2%), and CuOx (9.4%) under the same experimental conditions. We characterized the chemical compositions with XPS, crystal structures with XRD, and film morphology with SEM/AFM techniques. Photoluminescence (PL) spectra and the corresponding PL decays for perovskite deposited on varied HEL films were recorded to obtain the hole-extracting characteristics, for which the hole extracting times show the order CoOx (2.8 ns) < PEDOT:PSS (17.5 ns) < NiOx (22.8 ns) < CuOx (208.5 ns), consistent with the trend of their photovoltaic performances. The reproducibility and enduring stability of those devices were examined to show the outstanding long-term stability of the devices made of metal oxide HEL, for which the CoOx device retained PCE approximate to 12% for over 1000 h.
URI: http://dx.doi.org/10.1021/acsami.6b10803
ISSN: 1944-8244
DOI: 10.1021/acsami.6b10803
Volume: 8
Issue: 49
Begin Page: 33592
End Page: 33600
Appears in Collections:Articles