Transcript Slide 1

Surfaceplasmons in solar power
Enhancing Efficiency of Solar Cells and Solar Thermal
Collectors with surface Plasmon Resonances in Metal
Nanoparticles
Antti Pennanen, Jouko Korppi-Tommola & Jussi Toppari
8.6.2009
NSC
Nanoscience Center
UNIVERSITY OF JYVÄSKYLÄ
OSKE Beneq
Lamit.fi
Introduction
Properties of Silicon
• Abundant
• Cheap
• Stable
• Non-toxic
• Well-established industry
 Most used photovoltaic material
[Pillai et al. J.Appl.Phys. 101, 093105, 2007.]
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Introduction
Fig. 1: AM1.5 standard solar irradiance spectrum.
[Data from http://rredc.nrel.gov/solar/spectra/am1.5/]
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Introduction
Fig. 2: Optical absorption of silicon. [Shah, et al. Prog. Photovolt: Res. Appl. 12, 2004.]
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Introduction
• c-Si
– Expensive and difficult to fabricate
• a-Si & μc-Si
– Cheap
– High bulk recombination
 cell thickness must be kept small
• Low optical absorption above 750 nm
[Nelson: The Physics of Solar Cells, 2007.]
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Introduction
• Possible solution:
– Localized surface plasmons on metal
nanoparticles
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Localized Surface Plasmons
• Properties of sub-wavelength
metal particles
– Strong scattering and absorption
of EM radiation at certain
wavelengths
– Correspond to resonant
oscillations of e- gas
Localized surface plasmons
[Optical data from Johnson and Christy: Phys.Rev. B 6, no.12, 1972.]
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Localized Surface Plasmons
• Two ways to enhancement
– Scattering
– Absorption
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Localized Surface Plasmons
Scattering
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Localized Surface Plasmons
Excitation of Surface Plasmon
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Localized Surface Plasmons
Reradiation (scattering)
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Localized Surface Plasmons
Increased optical path
 Enhanced optical absorption
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Localized Surface Plasmons
Absorption
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Localized Surface Plasmons
Excitation of Surface Plasmon
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Localized Surface Plasmons
Enhanced electric field in the Si
 Direct generation of electron-hole pair
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Results:
• 8.1% increase in total short circuit
current output
• 8.3% increase in total power output
[Derkacs et al. Appl.Phys.Lett 89, 093103, 2006.]
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Results:
• 3 to 7 fold max enhancement in
photocurrent
• Up to 19% increase in total short
circuit current output
[Pillai et al. J.Appl.Phys.101, 093105, 2007.]
[Image of PERL cell: Zhao et al. Prog. Photovolt: Res. Appl. 7, 1999.]
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Results:
• 13 to 17 fold max enhancement in
photocurrent
• 16 to 33% increase in total short
circuit current output
[Pillai et al. J.Appl.Phys.101, 093105, 2007.]
[Image of SOI test device: Pillai et al. Appl.Phys.Lett. 88, 161102, 2006.]
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Results:
• 8.3% increase in total power output of aSi:H p-i-n test cell
[Derkacs et al. Appl.Phys.Lett. 89, 093103, 2006.]
• 16% increase in total photocurrent output
of a c-Si PERL cell
[Pillai et al. J.Appl.Phys.101, 093105, 2007.]
• 36% increase in total photocurrent output
of a SOI test cell
[Pillai et al. J.Appl.Phys.101, 093105, 2007.]
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Waveguide Solar Concentrator
• High-Efficiency Organic Solar Concentrators for
Photovoltaics by Organic dye Molecules
– Based on scattering to waveguide modes of the glass substrate
– Solar cells around the glass
– The dye-based organic solar concentrator functions without the
use of tracking or cooling systems
 greatly reduced the overall cost compared to other
concentrator technologies.
– Single- and tandem-waveguide organic solar concentrators with
quantum efficiencies exceeding 50%
[Michael J. Currie et al. Science 321, 226, 2008.]
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1. Dye molecules coated on glass absorb sunlight, and
re-emit it at a different wavelengths.
2. The light is trapped and transported within the glass
until it is captured by solar cells at the edge.
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Waveguide and LSP
• Metallic nanoparticles more robust than organic
molecules
• Absorption tunable via resonance frequency
• Efficient scattering into waveguide modes
– Proven by SOI solar cells before
• Suitable also for solar thermal?
 Integrable Solar Thermal or Photovoltaic unit
On-going Project: JYU/NSC, lamit.fi, Oske, Beneq
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Solar Power Market
• Approximately 10 GWh of solar thermal (ST) capacity
was in operation in Europe in 2005
• Estimated: Global ST capacity will reach 100 milj. m2
level by 2010 corresponding to 50 TWh per year
• Annual growth rate of ST business exceeds 20%
• Photovoltaics (PV) business and R&D field that is
growing extremely rapidly, up to 30% a year
• The total installed global PV power approaches 8000
MWp this year.
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Thank You
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