Supplementary Information
Single Junction Inverted Polymer Solar Cell Reaching Power Conversion
Efficiency 10.31% by Employing Dual-Doped Zinc Oxide Nano-Film as Cathode
Interlayer
Sih-Hao Liao, Hong-Jyun Jhuo, Po-Nan Yeh, Yu-Shan Cheng, Yi-Lun Li, Yu-Hsuan
Lee, Sunil Sharma, Show-An Chen*
Chemical Engineering Department and Frontier Research Center on Fundamental and
Applied Sciences of Matters, National Tsing-Hua University, Hsinchu 30013, Taiwan,
ROC
E-mail: sachen@che.nthu.edu.tw
Figure S1. The contact angle images by dropping DI water on the substrates
pre-cleaned by CS2/THF (1:1, v/v): (a) ITO/ZnO (40 nm), (b) ITO/InZnO (40 nm),
(c)ITO/ ZnO-BisC60 (40 nm), (d) ITO/InZnO-BisC60 (40 nm). The inset number on
the right-up corner is contact angle.
1
Figure S2. AFM (1x1 um) topographical images using tapping mode: (a) ZnO film,
(b) ZnO-BisC60 film with CS2 rinsing, (c) InZnO and (d) InZnO-BisC60 film with
CS2 rinsing. All the films were coated on ITO glass plate.
Figure S3. (a) UV-visible absorption spectra and (b) UPS spectra of cathode
interlayer (thin film) coated on ITO substrate. But the UV-visible spectrum of
BisNPC60-OH is from its solution in THF with 10-5 mol/L.
2
Figure S4. Current density versus bias voltage of the electron-only devices:
ITO/cathode interlayer /Ca (10 nm)/Al (100 nm).
Figure S5. J–V characteristics of PTB7-Th:PC71BM solar cells with (a) ZnO, (b)
InZnO, (c) InZnO-BisC60 as cathode interlayer under various light intensities ranging
from 100 mW/cm2 to 4.32 mW/cm2. (d) log-log plot of current density versus
irradiation light intensity.
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Figure S6. J–V characteristics of PTB7-Th:PC71BM solar cells with and without
shadow mask under one sun simulated 100 mW/cm2 AM 1.5G illumination.
Table S1. The HOMO level of cathode interlayer coated on ITO measured by use of
UPS (Figure S2b).
Sample structure
HOMO
level
(eV)
Optical band gap
(eV)
LUMO
level
(eV)
ITO/ZnO
ITO/InZnO
ITO/ZnO-BisC60
ITO/InZnO-BisC60
7.2
7.1
6.7
6.7
2.91
2.48
2.21
2.25
4.29
4.62
4.49
4.45
Optical band gap was determined from UV-vis absorption onset (Figure S2a).
LUMO level was determined by the relation: LUMO level = HOMO level – optical
band gap.
Table S2. Electron mobility of the cathode interlayers ZnO, InZnO and
InZnO-BisC60 determined using the electron-only device ITO/Cathode interlayer/Ca
(10 nm)/Al (100 nm) along with the use of space charge limited current equationa in
the calculation.
Cathode interlayer
Electron mobility (µ) (cm2 V-1 S-1)
ZnO
ZnO-BisC60
InZnO
InZnO-BisC60
8.25*10-5
6.21*10-3
9.51*10-3
1.09*10-2
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Table S3. Conductivity measurement using four probe method for the sample,
Glass/cathode interlayer (40 nm).
Conductivity (S cm-1)
Cathode interlayer
ZnO
ZnO-BisC60
InZnO
InZnO-BisC60
0.015
2.03
8.51
4.06
Table S4. i-PSC performance parameters for the devices ITO/Cathode interlayer
/PTB7-Th:PC71BM (1:1.5 w/w, 100 nm) /MoO3 (10 nm)/Ag (100 nm).
Cathode interlayer
Rsh
(Ωcm2)
Rs
(Ωcm2)
ZnO
ZnO-BisC60
InZnO
InZnO-BisC60
1120
1520
1290
1610
10.12
3.76
4.56
2.12
Rsh, shunt resistance, calculated from the inverse of slope of J-V curve at V = 0.S1,S2
Rs, series resistance, calculated from the inverse of slope of J-V curve at I = 0.S1,S2
References
S1 Yin, Z. et al. Graphene-Based Materials for Solar Cell Applications. Adv. Energy
Mater. DOI: 10.1002/aenm.201300574 (2014).
S2 Liao, H.-C. Diketopyrrolopyrrole-based oligomer modified TiO2 nanorods for
air-stable and all solution processed poly(3-hexylthiophene):TiO2 bulk
heterojunction inverted solar cell. J. Mater. Chem. 22, 10589-10596 (2012).
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