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Department of Energy Physics:

Experiences in PV

Alexander K. Fedotov fedotov@bsu.by

https://www.researchgate.net/profile/Alexander_Fedotov

https://www.researchgate.net/profile/Alexander_Mazanik

https://www.researchgate.net/profile/Mikhail_Tivanov

Belarusian State University Faculty of Physics

Department of Energy Physics

_____________________________________________________________

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Multi-crystalline silicon

[1] Grain boundary structure and electrical activity in shaped silicon / A. Fedotov, B. Evtody, L. Fionova, Yu. Iliashuk, E. Katz, L. Poljak // Journal of Crystal Growth. – 1990. – Vol. 104. – P. 186–190; [2] Electrical activity of grain boundaries in shaped grown silicon/ A. Fedotov, B. Evtody, L. Fionova, Yu. Iliashuk, E. Katz, L. Poljak // Physica Status Solidi (A). – 1990. – Vol. 119. – P. 523-534; [3] Carrier transport in heavily doped polycrystalline silicon layers after annealing by a scanning laser beam / A.K. Fedotov, M.I. Tarasik, A.M. Yanchenko // Applied Surface Science. – 1995. – Vol. 84. – P. 379-382; [4] Transformation of electrical activity of extended defects in silicon polycrystals under annealing and hydrogen plasma treatment / A. Fedotov, N. Drozdov, E. Katz, Yu. Ilyashuk, A. Mazanik, A. Ulyashin // Physica status solidi (a). – 1999. – Vol. 171. – P. 353–363; [5] Modification of electrical activity of grain boundaries in EFG silicon under influence of hydrogen plasma / A. Fedotov, A. Mazanik, E. Katz // Interface science. – 2001. – Vol. 9. – P. 169–173; [6] Electrical activity of grain boundaries in silicon bicrystals and its modification by hydrogen plasma treatment / A. Fedotov, A. Mazanik, A. Ulyashin // Solar Energy Materials and Solar Cells. – 2002. – Vol. 72. – P. 589–595; [7] Influence of low-energy ion-beam treatment by hydrogen on electrical activity of grain boundaries in polycrystalline silicon / A. Saad, A. Mazanik, A. Fedotov, J. Partyka, P. Węgierek, P. Żukovski // Vacuum. – 2005. – Vol. 78. – P. 269-272.

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1

3

5

7

3

1

No

rma

lize

d G

B c

on

ductivity

4

2

Hydrogenation time, min

3

Cu(In,Ga)(S,Se)2

[1] Photosensitivity of the structures on the Cu(In,Ga)(S,Se)2 films obtained by thermal treatment in the S and Se vapors / V.Yu. Rud’, M.S. Tivanov, Yu.V. Rud’, V.F. Gremenok, E.P. Zaretskaya, V.B. Zalesskii, T.R. Leonova, P.I. Romanov // Semiconductors. – 2007. – Vol. 41. – P. 1173 – 1177; [2] Cadmium-free thin-film Cu(In,Ga)Se2/(In2S3) heterophotoelements: fabrication and properties / V.B. Zalesskii, V.Yu. Rud’, V.F. Gremenok, Yu.V. Rud’, T.R. Leonova, A.V. Kravchenko, E.P. Zaretskaya, M.S. Tivanov // Semiconductors. – 2007. – Vol. 41. – P. 973 – 978; [3] Investigation of defects in Cu(In,Ga)(S,Se)2 films using the photocurrent decay technique / A. Saad, A. Odrinski, M. Tivanov, N. Drozdov, A. Fedotov, V. Gremenok, A. Mazanik, A. Patryn, V. Zalesski, E. Zaretskaya // Journal of Materials Science: Materials in Electronics. – 2008. – Vol. 19. – P. 371 – 374.

0,7 0,9 1,1 1,3 1,5 0,7 0,9 1,1 1,3 1,5 0,7 0,9 1,1 1,3 1,5

1

2

3

4

5

6

0

100

200

300

400

Eg, эВ Eg, эВ Eg, эВ(α

·hν)

2, (1

03·эВ·см

-1)2

1,0 мкм

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AIIBVI semiconductors

[1] Modification of electrical properties of CdSxSe1-x films by hard irradiation and nanostructuring / A.M. Saad, A.K. Fedotov, A.V. Mazanik, M.I. Tarasik, A.M. Yanchenko, A.S. Posedko, L.Y. Survilo, Yu.V. Trofimov, N.F. Kurilovich // Thin Solid Films. – 2005. – Vol. 487. – P. 202 – 204; [2] Optical and photoelectrical properties of CdSxSe1-x films produced by screen-printing technology / M. Tivanov, E. Ostretsov, N. Drozdov, L. Survilo, A. Fedotov, Yu. Trofimov, A. Mazanik // Physica status solidi (b). – 2007. – Vol. 244, No 5. – P. 1694 – 1699; [3] Electrical, photoelectrical, and photoelectrochemical properties of electrodeposited CdTe films subjected to high-energy irradiation / A.K. Fedotov, A.A. Ronassi, Vo Thi Tuiet Vi, A.V. Mazanik, O.V. Korolik, S.M. Rabchynski, G.A. Ragoisha, E.A. Streltsov // Thin Solid Films. – 2011. – Vol. 519. – P. 7149 – 7152.

20 30 40 50 60 700

1000

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3000

4000

5000

6000

CdTe CdTe

Ni

Ni

Cd

Te

Ni

CdTe

Inte

nsity, arb

. units

2

CdTe

(b)

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Nanostructured semiconductors,

composite materials for PV

[1] Photoelectrochemical and Raman characterization of In2O3 mesoporous films sensitized by CdS nanoparticles / N.V. Malashchonak, S.K. Poznyak, E.A. Streltsov, A.I. Kulak, O.V. Korolik, A.V. Mazanik // Beilstein Journal of Nanotechnology. – 2013. – Vol. 4. – P. 255 – 261; [2] Photoelectrochemical and Raman Characterization of Nanocrystalline CdS Grown on ZnO by Successive Ionic Layer Adsorption and Reaction Method / A.V. Kozitskiy, O.L. Stroyuk, S.Ya. Kuchmiy, A.V. Mazanik, S.K. Poznyak, Е.А. Streltsov, A.I. Kulak, O.V. Korolik, V.M. Dzhagan // Thin Solid Films. – 2014. – Vol. 562. – P. 56 – 62; [3] Band-gap and sub-band-gap photoelectrochemical processes at nanocrystalline CdS grown on ZnO by successive ionic layer adsorption and reaction method / M.V. Malashchonak, E.A. Streltsov, A.V. Mazanik, A.I. Kulak, S.K. Poznyak, O.L. Stroyuk, S.Ya. Kuchmiy, P.I. Gaiduk // Thin Solid Films. – 2015. – Vol. 589. – P. 145–152; [4] SnO2 / Reduced Graphene Oxide Composite Films for Electrochemical Applications / E.A. Bondarenko, A.V. Mazanik, Е.А. Streltsov, A.I. Kulak, O.V. Korolik // Materials Science and Engineering B. – 2015, DOI: 10.1016/j.mseb.2015.10.002; [6] Photocurrent switching effect on platelet-like BiOI electrodes: influence of redox system, light wavelength and thermal treatment / M.E. Kazyrevich, М.V. Malashchonak, A.V. Mazanik, E.A. Streltsov, A.I. Kulak, C. Bhattacharya // Electrochimica Acta (submitted).

Investigated objects: - Wide band-gap oxides sensitized by AIIBVI nanoparticles;

- Wide band-gap oxide / reduced graphene oxide

nanocomposites;

- BiOI layered semiconductors;

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Carbon materials

[1] Micro Raman investigation of graphene synthesized by atmospheric pressure CVD on copper foil from decane / I.V. Komissarov, N.G. Kovalchuk, E.A. Kolesov, M.S. Tivanov, O.V. Korolik, A.V. Mazanik, Yu.P. Shaman, A.S. Basaev, V.A. Labunov, S.L. Prischepa, N.I. Kargin, R.V. Ryzhuk, S.A. Shostachenko // Physics Procedia. – 2015. – Vol. 72. – P. 450–454; [2] The significant G peak temperature shift in Raman spectra of graphene on copper / M.S. Tivanov, A.G. Praneuski, E.A. Kolesov, O.V. Korolik, A.M. Saad, I.V. Komissarov, N.G. Kovalchuk // Physica Status Solidi B (submitted); [3] Raman spectra of graphene synthesized by chemical vapor deposition on copper foil using decane as precursor / M.S. Tivanov, E.A. Kolesov, O.V. Korolik, N.G. Kovalchuk, I.V. Komissarov, V.A. Labunov // Journal of Nanoscience and Nanotechnology (submitted).

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1604

1608

1612

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1620

G peak position

Linear approximation

Ram

an s

hif

t, c

m-1

Temperature, K

Slope Gcm

-1/K

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SC modelling and parameter calculations

[1] Determination of solar cell parameters from its current-voltage and spectral characteristics / M. Tivanov, A. Patryn, N. Drozdov, A. Fedotov, A. Mazanik // Solar Energy Materials & Solar Cells. – 2005. – Vol. 87. – P. 457–465; [2] Солнечные элементы на основе полупроводниковых материалов / В.Ф. Гременок, М.С. Тиванов, В.Б. Залесский. – Минск: Издательский центр БГУ, 2007. – 222 с; [3] Effect of absorbing layer thickness on efficiency of solar cells based on Cu(In,Ga)(S,Se)2

/ M. Tivanov, L. Astashenok, A. Fedotov // Electrical Review. - 2012. - Vol. 88, № 7a. - P. 321 - 323; [4] Determination of Cu(In,Ga)(S,Se)2-solar cell parameters from quantum efficiency spectra / M. Tivanov, A. Moskalev, A. Patryn // Electrical Review. - 2015. - Vol. 91, № 9. - P. 188 – 190.

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Calculation of solar cell parameters and operational characteristics

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Our equipment for testing of materials and structures

Confocal spectrometer «Nanofinder-HE»

for micro-Raman and micro-PL

measurements down to 20 K

Spatial resolution 200200500 nm3

Measuring system for electric

characterization of materials and

devices in AC/DC modes at 2-300 K

and magetic fields up to 8 T

Belarusian State University Faculty of Physics

Department of Energy Physics

_____________________________________________________________

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Belarusian State University Faculty of Physics

Department of Energy Physics

_____________________________________________________________

Development of equipment

for solar cell testing

I-V characteristics

Spectral characteristics

Lateral homogeneity (photo response

and temperature distribution)

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Possible participation in StableNextSol COST Action

We propose to use confocal micro-Raman/Pl spectrometer for spatial-resolved investigation of solar cell photodegradation. From this point of view, laser beam can be used:

(i) as a source of optical radiation with smoothly controlled

power density, which is able to cause SC photodegradation;

(ii) for local analysis of modification in structure of the region

subjected to high energy optical impact using Raman/PL

spectra with locality 200200500 nm;

(iii) for local measurement of SC parameters (short circuit

current, open circuit voltage, etc.) before and after high energy

optical impact.

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Alexander K. Fedotov fedotov@bsu.by

Thank you for

attention

Belarusian State University Faculty of Physics

Department of Energy Physics

_____________________________________________________________

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Quantum Dot Sensitized Solar Cell (QDSSC)

Electrons and holes photogenerated in nanoparticles can easily overcome a very small distance (a few nanometers) between the generation region and the photoanode/ electrolyte, so that even for small values of the mean lifetimes they do not recombine.

It makes possible to obtain high

efficiency values even using defective materials.

The main idea of slide – the effective use of spatial organization in QDSSCs:

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Quantum Dot Sensitized Solar Cell (QDSSC)

• Possibility to control spectral range of photosensitivity varying QDs’ size;

• QDs can be synthesized using cheap wet chemistry methods;

• Spatial organization of QDSSCs allows to reach high photosensitivity using highly defective absorber materials

Main Advantages:

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Photoanode materials: In2O3 mesoporous films (a), arrays of TiO2 nanotubes (b),

mesoporous ZnO micro-platelets (c)

The BET specific surface area is equal to 119±8 m2/g for In2O3 and 105±12 m2/g for ZnO. The specific surface area estimated from SEM results for the TiO2 nanotube array is about 10 m2/g.

(b) (a) (c)

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The main idea of this slide - photoanode must have a high specific surface area, so it could be joined with a lot of

nanoparticles and ensure the effective absorption of light

The BET specific surface area is equal to 119±8 m2/g for In2O3 and 105±12 m2/g for ZnO. The specific surface area estimated from SEM

results for the TiO2 nanotube array is about 10 m2/g

(b) (a) (c)

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Photocurrent spectra of CdS/ZnO films confirm that we really can achieve high values of the quantum

efficiency of the photoelectric conversion

Spectral dependences of External Quantum Efficiency Y presented in the coordinates Y – λ (a) and (Y∙hn)2 – hn (b) for different electrodes: ZnO (1) and

ZnO/CdS (2-6) at SILAR cycle number N = 5 (2), 10 (3), 20 (4), 60 (5) and 200 (6)

350 400 450 500 550 6000,0

0,2

0,4

0,6

0,8

1,0

Exte

rnal Q

uantu

m E

ffic

iency Y

Wavelength , nm

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2

3 45

6

2,2 2,4 2,6 2,8 3,0 3,2 3,40

1

2

3

4

5

(Yhn)2

hn, eV

12

36

45

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ZnO: indirect electrochemical deposition (growth of

Zn5(OH)8Cl2 with subsequent heat treatment leading

to ZnO formation);

In2O3: deposition of indium hydroxide colloidal solution

with a subsequent heat treatment ;

TiO2: anodization of metallic titanium

CdS nanoparticles: SILAR technique – sequential

immersion of substrate in Cd(NO3)2 alcohol solution,

rinsing in distilled water, immersion in Na2S aqueous

solution and the subsequent washing in distilled

water.

The cycle is repeated 5 - 300 times.

Methods of synthesis:

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Max power:

20 mW (for 532 nm)

8 mW (for 473 nm)

2 mW (for 355 nm)

The attenuation coefficient - from 1E-6 to 1.

Belarusian State University Faculty of Physics

Department of Energy Physics

_____________________________________________________________