Light-soaking issues in stability
determination of organic solar cells and
calcium test for low-cost barrier layers
Michal Dusza, Jonatan Stoklosa, Filip Granek
COST Meeting
E-MRS, 12.05.2015
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OUTLINE
Outline
1. Laboratory for Printed Electronics and Solar Cells,
Wroclaw Research Centre EIT+
2. Light-soaking issues in stability
determination of organic solar cells
3. Calcium test for low-cost barrier layers
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WROCLAW RESEARCH CENTRE EIT+
LABORATORY FOR PRINTED ELECTRONICS
AND SOLAR CELLS
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WROCLAW RESEARCH CENTRE EIT+
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WROCLAW RESEARCH CENTRE EIT+
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WROCLAW RESEARCH CENTRE EIT+
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LABORATORY FOR PRINTED ELECTRONICS AND SOLAR CELLS
RESEARCH EQUIPMENT
Prototype Structures
Advanced Printing Techniques Characterization and Modelling
- glove-box with integrated
- ink-jet printer PixDro LP50
- sun simulator AAA
vaccum chamber (6 thermal
- bentham (EQE, IQE)
sources (2 for organic
- filmetrics (T, R, R70)
materials) and e-beam)
- numerical model
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LABORATORY FOR PRINTED ELECTRONICS AND SOLAR CELLS
RESEARCH TEAM
Mix of competences: physics, microsystems, photonics, chemistry,
electronics
Team members:
Andrzej Chuchmala PhD
Marcin Palewicz PhD
Michal Dusza MSc
Filip Granek PhD
Magdalena Wozniak MSc
Kamila Startek MSc
Mariusz Prorok MSc
Jonatan Stoklosa
Orest Andriyishyn
Students:
Lukasz Baisinger
Mateusz Lysien
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LABORATORY FOR PRINTED ELECTRONICS AND SOLAR CELLS
MAIN ACTIVITIES IN SOLAR CELLS FIELD
Optical and
Electrical Modelling
CIS/CIGS
nanoparticle and Solar Cell processing
quantum dot
synthesis
Characterization
and degradation studies
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LABORATORY FOR PRINTED ELECTRONICS AND SOLAR CELLS
Acquired and currently executed
research projects by the laboratory team
Granting agency
Project title
Flexible organic solar cells free from ITO
Novel third generation thin-film solar cells based on
organic and inorganic nanomaterials
NCBR
NCBR
Flexible polymer solar cells with improved long-term
stability
Project partner in: Organic solar cells based on novel
polithiophenes and poliazomethines
Stable Next Generation Photovoltaics: Unravelling
degradation mechanisms of Organic Solar Cells by
complementary characterization techniques)
Industrial project
Research on Dye-Sentitized Solar Cells DSSC
Industrial cooperation
Research on Perovskite Solar Cells
Light-soaking issues in stability determination
of organic solar cells
Light-soaking effect
Short exposure to the light (few minutes)
before the I-V measurement improves the
photovoltaics properties of solar cells
Trap states at interfaces (ITO/metal oxide or
metal oxide/BHJ)
Illumination fills the trap states and changes
the energy levels – no barriers for free
charge carriers
A.Manor et al. Solar Energy Materials & Solar Cells 98, 2012, 491–493
F.J. Lim et al. Journal of Materials Chemistry A, 2015,3, 314-322
Light-soaking issues in stability determination
of organic solar cells
Motivation
• Efficiency and stability determination
• Saturation time of light-soaking effect
• Light-soaking induce the degradation
• Effect of light-soaking is increasing/decresing with
degradation
• Light-soaking coefficient – ratio between the
parameter measured after light-soaking and the
parameter measured of dark stored sample (before
light-soaking)
Light-soaking issues in stability determination
of organic solar cells
Motivation
• Effect of light-soaking - increasing or
decreasing with degradation?
• Theoretical possibilities:
•Constant with time
•Decreasing with time
•Increasingwith time
Light-soaking issues in stability determination
of organic solar cells
Device fabrication
5 groups of organic solar cells – non-annealed and 4 various
temperatures of annealing the BHJ
• Various level of PCBM agglomeration
• Various qualities of solar cells
110oC
150oC
130oC
170oC
Light-soaking issues in stability determination
of organic solar cells
Investigation of light-soaking effect
Repeated up to
10 min of total
light-soaking time
•
•
•
•
sweep I-V curve (dark stored samples)
2 min light-soaking under sun simulator
20 s in the dark (cooling down sample and photodetector)
sweep I-V curve (light-soaked samples)
Light-soaking issues in stability determination
of organic solar cells
Light-soaking issues in stability determination
of organic solar cells
Light-soaking changes each PV
parameter
The weaker samples are the better
of improvement we get after lightsoaking
10-35% of efficiency improvment
after 10 min light-soaking
Light-soaking issues in stability determination
of organic solar cells
Light-soaking induce the degradation
Two types of samples
1. No exposure for light except during the sweep I-V curve (always stored in the dark)
2. 10 min cycles of light-soaking in during each measurement day
Parameters without light-soaking
Light-soaking issues in stability determination
of organic solar cells
Light-soaking induce the degradation
Two types of samples
1. No exposure for light except during the sweep I-V curve (always stored in the dark)
2. 10 min cycles of light-soaking in during each measurement day
Parameters without light-soaking
Light-soaking issues in stability determination
of organic solar cells
Stability determination with/without light-soaking
Light-soaking issues in stability determination
of organic solar cells
Light-soaking coefficient
Light-soaking coefficient – Describes how strong is improvement of properties
due to light-soaking
Ratio between efficiency (or other parameter) measured after 10 min of lightsoaking and efficiency measured of dark stored sample
Light-soaking issues in stability determination
of organic solar cells
Light-soaking coefficient
Light-soaking coefficient – Describes how strong is improvement of properties
The weaker samples are the better
due to light-soaking
of other
improvement
we measured
get after lightRatio between efficiency (or
parameter)
after 10 min of lightsoaking and efficiency measured of darksoaking
stored sample
10-35% of efficiency improvment
after 10 min light-soaking (day 0)
25-65% of efficiency improvment
after 10 min light-soaking (day 10)
Improvement due to light-soaking
increases with degradation/time
Light-soaking issues in stability determination
of organic solar cells
Summarize the light-soaking
• Light exposure (light-soaking)
induce the degradation
• Light-soaking effect is changing in
time (increasing)
• Light-soaking reduce the negative
impact of light exposure
• The better solar cell is the less
improvement due to light-soaking is
observing
Poster session E-MRS EP2 33
LIGHT-SOAKING EFFECT OF AGED ITO-FREE INVERTED ORGANIC SOLAR CELLS WITH
ALUMINUM-DOPED ZINC OXIDE ELECTRODE GROWN BY ATOMIC LAYER DEPOSITION
Calcium test for low-cost barrier layers
Ca
conducting and
non-transparent
Ca(OH)2
non-conducting and
transparent
S. Schubert et al., Review of Scientific Instruments, 82, 094101, 2011
Calcium test for low-cost barrier layers
Water Vapor Transmission Rate [g/(day*m2)]
Calcium tests - development technology in our laboratory
based on S. Schubert et al. work.
Testing low-cost barriers based on hybrid glasses (sol-gel
method, deposited on PET foils)
Improvement of PET foil barrier properties as a substrate for
organic (polymer) / perovskite / hybrid (CIS NPs) solar cells
0h
after 10 h
after 15 h
after 20 h
after 30 h
S. Schubert et al., Review of Scientific Instruments, 82, 094101, 2011
Calcium test for low-cost barrier layers
- First results were obtained
- Reproducible measurement and
sample preparation
- Problems with barriers – not
much increasing the WVTR of PET
- Phenomena of decreasing
resistance in time
- Automatic measurement of 12
samples (possibility to easly
increase)
- Parrarel resistance and
transmitance/reflectance
measurement of 1 sample
(electrical and optical calcium test)
Acknowledgments
The work was supported by the National Centre for Research and Development (NCBR) within
the Project POSCIS (grant aggrement no. LIDER/09/129/L-3/11/NCBR/2012)
WROCLAW RESEARCH CENTRE EIT+
Thank You for Your Attention!
Contacts: [email protected]
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