Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Grätzel Solar Cell

Gabor Benko

Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Grätzel Solar Cell

Gabor Benko

Chemical Physics

Research output: Thesis › Doctoral Thesis (compilation)

Abstract

The key materials used to convert solar energy into electricity in the Grätzel-type solar cells are dye molecules and titanium dioxide particles attached to each other. The former are similar to those in common products like purple pigments in blueberry juice, while the latter are like sunscreen, white paint, or toothpaste. Their size, measured in nanometers, is a hundred thousand times smaller than a strand of hair.

This thesis presents a series of investigations that attempt to give a better understanding of how the dye molecules, energized by sunlight, inject electrons into the titanium dioxide particles, which is an essential reaction in the functioning of the solar cell. As this reaction is one of the fastest ever studied, we have to use the world’s fastest camera. This camera uses laser flashes as short or even shorter in duration as the speed of the reaction, which occurs already in femtoseconds. One femtosecond is 10-15 seconds, that is, 0.000000000000001 seconds, which is to a second as a second is to 32 million years. With such a camera we are able to monitor the track of the electron in slow motion. We have seen for several dye molecule-titanium dioxide particle couples how the electron leaves the molecule and arrives into the particle as early as femtoseconds after laser flash illumination. For certain systems, the electron goes back to the dye molecule immediately after being injected in the titanium dioxide particle, without performing work in an outer electrical circuit. Obviously, those dyes are not suitable for the solar cell. The ultimate goal is to fully understand the mechanism of the electron transfer reaction, and according to the findings modify the materials to show better performance in the solar cell.

Original language	English
Qualification	Doctor
Awarding Institution	Chemical Physics
Supervisors/Advisors	[unknown], [unknown], Supervisor, External person
Award date	2003 Feb 7
Publisher	Chemical Physics, Lund University
ISBN (Print)	91-628-5524-7
Publication status	Published - 2003

Bibliographical note

Defence details

Date: 2003-02-07
Time: 10:30
Place: Chemical Center, lecture hall B,

External reviewer(s)

Name: Moser, Jacques-E.
Title: PD Dr
Affiliation: [unknown]

---

Article: I. Electron Injection and Recombination in Fluorescein 27-Sensitized TiO2 Thin Films, Benkö, G.; Hilgendorff, M.; Yartsev, A. P.; Sundström, V. J. Phys. Chem. B 2001, 105, 967-974.

Article: II. Modified Phthalocyanines for Efficient Near-IR Sensitization of Nanostructured TiO2 Electrode, He, J.; Benkö, G.; Korodi, F.; Polivka, T.; Lomoth, R.; Akermark, B.; Sun, L.; Hagfeldt, A.; Sundström, V. J. Am. Chem. Soc. 2002, 124, 4922-4932.

Article: III. Photoinduced Ultrafast Dye-to-Semiconductor Electron Injection from Nonthermalized and Thermalized Donor States, Benkö, G.; Kallioinen, J.; Korppi-Tommola, J. E. I.; Yartsev, A. P.; Sundström, V. J. Am. Chem. Soc. 2002, 124, 489-493.

Article: IV. Electron Transfer from the Singlet and Triplet Excited States of Ru(dcbpy)2(NCS)2 into Nanocrystalline TiO2 Thin Films, Kallioinen, J.; Benkö, G.; Sundström, V.; Korppi-Tommola, J. E. I.; Yartsev, A. P. J. Phys. Chem. B 2002, 106, 4396-4404.

Article: V. Photoinduced Electron Transfer Between a Carotenoid and TiO2 Nanoparticle, Pan, J.; Benkö, G.; Xu, Y.; Pascher, T.; Sun, L.; Sundström V.; Polívka, T. J. Am. Chem. Soc. 2002, 124, 13949-13957.

Article: VI. Particle Size and Crystallinity Dependent Electron Injection in Fluorescein 27-Sensitized TiO2 Films, Benkő, G.; Skårman, B.; Wallenberg, R.; Hagfeldt, A.; Sundström, V.; Yartsev, A. P. J. Phys. Chem. B 2003, in press.

Article: VII. Photoinduced Electron Injection from Ru(dcbpy)2(NCS)2 to SnO2 and TiO2 Nanocrystalline Films, Benkö, G.; Myllyperkiö, P.; Pan, J.; Yartsev, A.P.; Sundström, V. J. Am. Chem. Soc. 2003, in press.

The information about affiliations in this record was updated in December 2015.
The record was previously connected to the following departments: Chemical Physics (S) (011001060)

Subject classification (UKÄ)

Atom and Molecular Physics and Optics

Free keywords

supraledare
magnetisk resonans
spektroskopi
magnetiska och optiska)
egenskaper (elektriska
Kondenserade materiens egenskaper:elektronstruktur
spectroscopy
relaxation
magnetic resonance
supraconductors
Kemi
Condensed matter:electronic structure
electrical
femtosecond spectroscopy
solar cells
Chemistry
excited states
photoinduced electron transfer
transition metal complexes
nanocrystalline titanium dioxide
dye sensitization
porous semiconductor film
magnetic and optical properties

Cite this

@phdthesis{bc75bba1c1e84882ac5a0668f4faef54,

title = "Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Gr{\"a}tzel Solar Cell",

abstract = "The key materials used to convert solar energy into electricity in the Gr{\"a}tzel-type solar cells are dye molecules and titanium dioxide particles attached to each other. The former are similar to those in common products like purple pigments in blueberry juice, while the latter are like sunscreen, white paint, or toothpaste. Their size, measured in nanometers, is a hundred thousand times smaller than a strand of hair. This thesis presents a series of investigations that attempt to give a better understanding of how the dye molecules, energized by sunlight, inject electrons into the titanium dioxide particles, which is an essential reaction in the functioning of the solar cell. As this reaction is one of the fastest ever studied, we have to use the world{\textquoteright}s fastest camera. This camera uses laser flashes as short or even shorter in duration as the speed of the reaction, which occurs already in femtoseconds. One femtosecond is 10-15 seconds, that is, 0.000000000000001 seconds, which is to a second as a second is to 32 million years. With such a camera we are able to monitor the track of the electron in slow motion. We have seen for several dye molecule-titanium dioxide particle couples how the electron leaves the molecule and arrives into the particle as early as femtoseconds after laser flash illumination. For certain systems, the electron goes back to the dye molecule immediately after being injected in the titanium dioxide particle, without performing work in an outer electrical circuit. Obviously, those dyes are not suitable for the solar cell. The ultimate goal is to fully understand the mechanism of the electron transfer reaction, and according to the findings modify the materials to show better performance in the solar cell.",

keywords = "supraledare, magnetisk resonans, spektroskopi, magnetiska och optiska), egenskaper (elektriska, Kondenserade materiens egenskaper:elektronstruktur, spectroscopy, relaxation, magnetic resonance, supraconductors, Kemi, Condensed matter:electronic structure, electrical, femtosecond spectroscopy, solar cells, Chemistry, excited states, photoinduced electron transfer, transition metal complexes, nanocrystalline titanium dioxide, dye sensitization, porous semiconductor film, magnetic and optical properties",

author = "Gabor Benko",

note = "Defence details Date: 2003-02-07 Time: 10:30 Place: Chemical Center, lecture hall B, External reviewer(s) Name: Moser, Jacques-E. Title: PD Dr Affiliation: [unknown] --- Article: I. Electron Injection and Recombination in Fluorescein 27-Sensitized TiO2 Thin Films, Benk{\"o}, G.; Hilgendorff, M.; Yartsev, A. P.; Sundstr{\"o}m, V. J. Phys. Chem. B 2001, 105, 967-974. Article: II. Modified Phthalocyanines for Efficient Near-IR Sensitization of Nanostructured TiO2 Electrode, He, J.; Benk{\"o}, G.; Korodi, F.; Polivka, T.; Lomoth, R.; Akermark, B.; Sun, L.; Hagfeldt, A.; Sundstr{\"o}m, V. J. Am. Chem. Soc. 2002, 124, 4922-4932. Article: III. Photoinduced Ultrafast Dye-to-Semiconductor Electron Injection from Nonthermalized and Thermalized Donor States, Benk{\"o}, G.; Kallioinen, J.; Korppi-Tommola, J. E. I.; Yartsev, A. P.; Sundstr{\"o}m, V. J. Am. Chem. Soc. 2002, 124, 489-493. Article: IV. Electron Transfer from the Singlet and Triplet Excited States of Ru(dcbpy)2(NCS)2 into Nanocrystalline TiO2 Thin Films, Kallioinen, J.; Benk{\"o}, G.; Sundstr{\"o}m, V.; Korppi-Tommola, J. E. I.; Yartsev, A. P. J. Phys. Chem. B 2002, 106, 4396-4404. Article: V. Photoinduced Electron Transfer Between a Carotenoid and TiO2 Nanoparticle, Pan, J.; Benk{\"o}, G.; Xu, Y.; Pascher, T.; Sun, L.; Sundstr{\"o}m V.; Pol{\'i}vka, T. J. Am. Chem. Soc. 2002, 124, 13949-13957. Article: VI. Particle Size and Crystallinity Dependent Electron Injection in Fluorescein 27-Sensitized TiO2 Films, Benk{\H o}, G.; Sk{\aa}rman, B.; Wallenberg, R.; Hagfeldt, A.; Sundstr{\"o}m, V.; Yartsev, A. P. J. Phys. Chem. B 2003, in press. Article: VII. Photoinduced Electron Injection from Ru(dcbpy)2(NCS)2 to SnO2 and TiO2 Nanocrystalline Films, Benk{\"o}, G.; Myllyperki{\"o}, P.; Pan, J.; Yartsev, A.P.; Sundstr{\"o}m, V. J. Am. Chem. Soc. 2003, in press. The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Physics (S) (011001060)",

year = "2003",

language = "English",

isbn = "91-628-5524-7",

publisher = "Chemical Physics, Lund University",

type = "Doctoral Thesis (compilation)",

school = "Chemical Physics",

}

TY - THES

T1 - Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Grätzel Solar Cell

AU - Benko, Gabor

N1 - Defence details Date: 2003-02-07 Time: 10:30 Place: Chemical Center, lecture hall B, External reviewer(s) Name: Moser, Jacques-E. Title: PD Dr Affiliation: [unknown] --- Article: I. Electron Injection and Recombination in Fluorescein 27-Sensitized TiO2 Thin Films, Benkö, G.; Hilgendorff, M.; Yartsev, A. P.; Sundström, V. J. Phys. Chem. B 2001, 105, 967-974. Article: II. Modified Phthalocyanines for Efficient Near-IR Sensitization of Nanostructured TiO2 Electrode, He, J.; Benkö, G.; Korodi, F.; Polivka, T.; Lomoth, R.; Akermark, B.; Sun, L.; Hagfeldt, A.; Sundström, V. J. Am. Chem. Soc. 2002, 124, 4922-4932. Article: III. Photoinduced Ultrafast Dye-to-Semiconductor Electron Injection from Nonthermalized and Thermalized Donor States, Benkö, G.; Kallioinen, J.; Korppi-Tommola, J. E. I.; Yartsev, A. P.; Sundström, V. J. Am. Chem. Soc. 2002, 124, 489-493. Article: IV. Electron Transfer from the Singlet and Triplet Excited States of Ru(dcbpy)2(NCS)2 into Nanocrystalline TiO2 Thin Films, Kallioinen, J.; Benkö, G.; Sundström, V.; Korppi-Tommola, J. E. I.; Yartsev, A. P. J. Phys. Chem. B 2002, 106, 4396-4404. Article: V. Photoinduced Electron Transfer Between a Carotenoid and TiO2 Nanoparticle, Pan, J.; Benkö, G.; Xu, Y.; Pascher, T.; Sun, L.; Sundström V.; Polívka, T. J. Am. Chem. Soc. 2002, 124, 13949-13957. Article: VI. Particle Size and Crystallinity Dependent Electron Injection in Fluorescein 27-Sensitized TiO2 Films, Benkő, G.; Skårman, B.; Wallenberg, R.; Hagfeldt, A.; Sundström, V.; Yartsev, A. P. J. Phys. Chem. B 2003, in press. Article: VII. Photoinduced Electron Injection from Ru(dcbpy)2(NCS)2 to SnO2 and TiO2 Nanocrystalline Films, Benkö, G.; Myllyperkiö, P.; Pan, J.; Yartsev, A.P.; Sundström, V. J. Am. Chem. Soc. 2003, in press. The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Chemical Physics (S) (011001060)

PY - 2003

Y1 - 2003

N2 - The key materials used to convert solar energy into electricity in the Grätzel-type solar cells are dye molecules and titanium dioxide particles attached to each other. The former are similar to those in common products like purple pigments in blueberry juice, while the latter are like sunscreen, white paint, or toothpaste. Their size, measured in nanometers, is a hundred thousand times smaller than a strand of hair. This thesis presents a series of investigations that attempt to give a better understanding of how the dye molecules, energized by sunlight, inject electrons into the titanium dioxide particles, which is an essential reaction in the functioning of the solar cell. As this reaction is one of the fastest ever studied, we have to use the world’s fastest camera. This camera uses laser flashes as short or even shorter in duration as the speed of the reaction, which occurs already in femtoseconds. One femtosecond is 10-15 seconds, that is, 0.000000000000001 seconds, which is to a second as a second is to 32 million years. With such a camera we are able to monitor the track of the electron in slow motion. We have seen for several dye molecule-titanium dioxide particle couples how the electron leaves the molecule and arrives into the particle as early as femtoseconds after laser flash illumination. For certain systems, the electron goes back to the dye molecule immediately after being injected in the titanium dioxide particle, without performing work in an outer electrical circuit. Obviously, those dyes are not suitable for the solar cell. The ultimate goal is to fully understand the mechanism of the electron transfer reaction, and according to the findings modify the materials to show better performance in the solar cell.

AB - The key materials used to convert solar energy into electricity in the Grätzel-type solar cells are dye molecules and titanium dioxide particles attached to each other. The former are similar to those in common products like purple pigments in blueberry juice, while the latter are like sunscreen, white paint, or toothpaste. Their size, measured in nanometers, is a hundred thousand times smaller than a strand of hair. This thesis presents a series of investigations that attempt to give a better understanding of how the dye molecules, energized by sunlight, inject electrons into the titanium dioxide particles, which is an essential reaction in the functioning of the solar cell. As this reaction is one of the fastest ever studied, we have to use the world’s fastest camera. This camera uses laser flashes as short or even shorter in duration as the speed of the reaction, which occurs already in femtoseconds. One femtosecond is 10-15 seconds, that is, 0.000000000000001 seconds, which is to a second as a second is to 32 million years. With such a camera we are able to monitor the track of the electron in slow motion. We have seen for several dye molecule-titanium dioxide particle couples how the electron leaves the molecule and arrives into the particle as early as femtoseconds after laser flash illumination. For certain systems, the electron goes back to the dye molecule immediately after being injected in the titanium dioxide particle, without performing work in an outer electrical circuit. Obviously, those dyes are not suitable for the solar cell. The ultimate goal is to fully understand the mechanism of the electron transfer reaction, and according to the findings modify the materials to show better performance in the solar cell.

KW - supraledare

KW - magnetisk resonans

KW - spektroskopi

KW - magnetiska och optiska)

KW - egenskaper (elektriska

KW - Kondenserade materiens egenskaper:elektronstruktur

KW - spectroscopy

KW - relaxation

KW - magnetic resonance

KW - supraconductors

KW - Kemi

KW - Condensed matter:electronic structure

KW - electrical

KW - femtosecond spectroscopy

KW - solar cells

KW - Chemistry

KW - excited states

KW - photoinduced electron transfer

KW - transition metal complexes

KW - nanocrystalline titanium dioxide

KW - dye sensitization

KW - porous semiconductor film

KW - magnetic and optical properties

M3 - Doctoral Thesis (compilation)

SN - 91-628-5524-7

PB - Chemical Physics, Lund University

ER -

Dynamics of Photoinduced Processes in Dye-Sensitized Nanocrystalline Semiconductor Films--Reactions in the Photoactive Part of the Grätzel Solar Cell

Abstract

Bibliographical note

Subject classification (UKÄ)

Free keywords

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Cite this