Single-Walled Carbon Nanotube Film as Electrode in Indium-Free Planar Heterojunction Perovskite Solar Cells: Investigation of Electron-Blocking Layers and Dopants.
In this work, we fabricated indium-free perovskite solar cells (SCs) using direct- and dry-transferred aerosol single-walled carbon nanotubes (SWNTs). We investigated diverse methodologies to solve SWNTs' hydrophobicity and doping issues in SC devices. These include changing wettability of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (
PSS), MoO3 thermal doping, and HNO3(aq) doping with various dilutions from 15 to 70 v/v% to minimize its instability and toxic nature. We discovered that isopropanol (IPA) modified
PSS works better than surfactant modified
PSS as an electron-blocking layer on SWNTs in perovskite SCs due to superior wettability, whereas MoO3 is not compatible owing to energy level mismatching. Diluted HNO3 (35 v/v%)-doped SWNT-based device produced the highest PCE of 6.32% among SWNT-based perovskite SCs, which is 70% of an indium tin oxide (ITO)-based device (9.05%). Its flexible application showed a PCE of 5.38% on polyethylene terephthalate (PET) substrate.
Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Il
I
Jeon
Department of Mechanical Engineering, School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Takaaki
T
Chiba
Department of Mechanical Engineering, School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Clement
C
Delacou
Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Yunlong
Y
Guo
Department of Applied Physics, Aalto University School of Science , 15100, FI-00076 Aalto, Finland.
Antti
A
Kaskela
Department of Applied Physics, Aalto University School of Science , 15100, FI-00076 Aalto, Finland.
Olivier
O
Reynaud
Department of Applied Physics, Aalto University School of Science , 15100, FI-00076 Aalto, Finland.
Esko I
EI
Kauppinen
Department of Mechanical Engineering, School of Engineering, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.|National Institute of Advanced Industrial Science and Technology (AIST) , 1-2-1 Namiki, Tsukuba 305-8564, Japan.
Shigeo
S
Maruyama
Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Yutaka
Y
Matsuo
ITO-free; MoO3 doping; PEDOT:PSS modification; carbon nanotube; flexible solar cell; perovskite solar cell