Photoelectrochemistry of Langmuir-Blodgett films of carotenoid pigments on ITO electrodes

Leonides Sereno, Juana J. Silber, Luís Otero, María Del Valle Bohorquez, Ana L Moore, Thomas A Moore, John Devens Gust

Research output: Contribution to journalArticle

86 Citations (Scopus)

Abstract

Langmuir-Blodgett (LB) films of an amphipathic carotenoid, 7′-apo-7′-(4-carboxyphenyl)-β-carotene (ACC), were deposited on semiconducting transparent ITO electrodes which were then immersed in electrolyte containing benzoquinone (Q) or hydroquinone (QH2). Photocurrents were measured over the spectral range 350-700 nm. The action spectra implicate the excited carotenoid pigment, possibly in an aggregated form, as the photoactive species in the photoinduced electron transfer process. The photocurrents (up to 2 nA/cm2) were proportional to the light intensity and the number of deposited layers. The quantum yield of electron transfer was found to be independent of the number of layers, which implies efficient charge transfer between the layers. This result is unique to these carotenoid films. The polyenic carboxylic acid behaves as a photoconductor, in contrast to saturated long-chain acids which act as insulators in similar experiments. The direction of the photocurrent was investigated as a function of the bias potential, as well as the concentration of QH2 and Q in the surrounding electrolyte. In the presence of a large excess of QH2 the photocurrent was anodic, but it was cathodic in the presence of a large excess of Q.

Original languageEnglish
Pages (from-to)814-821
Number of pages8
JournalJournal of Physical Chemistry
Volume100
Issue number2
Publication statusPublished - Jan 11 1996

Fingerprint

photoelectrochemistry
carotenoids
Langmuir Blodgett films
Carotenoids
Langmuir-Blodgett films
pigments
ITO (semiconductors)
Photocurrents
Pigments
photocurrents
Electrodes
electrodes
Electrolytes
electron transfer
electrolytes
Photoconducting materials
carotene
photoconductors
Electrons
quinones

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Engineering(all)

Cite this

Photoelectrochemistry of Langmuir-Blodgett films of carotenoid pigments on ITO electrodes. / Sereno, Leonides; Silber, Juana J.; Otero, Luís; Del Valle Bohorquez, María; Moore, Ana L; Moore, Thomas A; Gust, John Devens.

In: Journal of Physical Chemistry, Vol. 100, No. 2, 11.01.1996, p. 814-821.

Research output: Contribution to journalArticle

Sereno, Leonides ; Silber, Juana J. ; Otero, Luís ; Del Valle Bohorquez, María ; Moore, Ana L ; Moore, Thomas A ; Gust, John Devens. / Photoelectrochemistry of Langmuir-Blodgett films of carotenoid pigments on ITO electrodes. In: Journal of Physical Chemistry. 1996 ; Vol. 100, No. 2. pp. 814-821.
@article{e3f851224382441da40aeffcd0c1c2ff,
title = "Photoelectrochemistry of Langmuir-Blodgett films of carotenoid pigments on ITO electrodes",
abstract = "Langmuir-Blodgett (LB) films of an amphipathic carotenoid, 7′-apo-7′-(4-carboxyphenyl)-β-carotene (ACC), were deposited on semiconducting transparent ITO electrodes which were then immersed in electrolyte containing benzoquinone (Q) or hydroquinone (QH2). Photocurrents were measured over the spectral range 350-700 nm. The action spectra implicate the excited carotenoid pigment, possibly in an aggregated form, as the photoactive species in the photoinduced electron transfer process. The photocurrents (up to 2 nA/cm2) were proportional to the light intensity and the number of deposited layers. The quantum yield of electron transfer was found to be independent of the number of layers, which implies efficient charge transfer between the layers. This result is unique to these carotenoid films. The polyenic carboxylic acid behaves as a photoconductor, in contrast to saturated long-chain acids which act as insulators in similar experiments. The direction of the photocurrent was investigated as a function of the bias potential, as well as the concentration of QH2 and Q in the surrounding electrolyte. In the presence of a large excess of QH2 the photocurrent was anodic, but it was cathodic in the presence of a large excess of Q.",
author = "Leonides Sereno and Silber, {Juana J.} and Lu{\'i}s Otero and {Del Valle Bohorquez}, Mar{\'i}a and Moore, {Ana L} and Moore, {Thomas A} and Gust, {John Devens}",
year = "1996",
month = "1",
day = "11",
language = "English",
volume = "100",
pages = "814--821",
journal = "Journal of Physical Chemistry",
issn = "0022-3654",
publisher = "American Chemical Society",
number = "2",

}

TY - JOUR

T1 - Photoelectrochemistry of Langmuir-Blodgett films of carotenoid pigments on ITO electrodes

AU - Sereno, Leonides

AU - Silber, Juana J.

AU - Otero, Luís

AU - Del Valle Bohorquez, María

AU - Moore, Ana L

AU - Moore, Thomas A

AU - Gust, John Devens

PY - 1996/1/11

Y1 - 1996/1/11

N2 - Langmuir-Blodgett (LB) films of an amphipathic carotenoid, 7′-apo-7′-(4-carboxyphenyl)-β-carotene (ACC), were deposited on semiconducting transparent ITO electrodes which were then immersed in electrolyte containing benzoquinone (Q) or hydroquinone (QH2). Photocurrents were measured over the spectral range 350-700 nm. The action spectra implicate the excited carotenoid pigment, possibly in an aggregated form, as the photoactive species in the photoinduced electron transfer process. The photocurrents (up to 2 nA/cm2) were proportional to the light intensity and the number of deposited layers. The quantum yield of electron transfer was found to be independent of the number of layers, which implies efficient charge transfer between the layers. This result is unique to these carotenoid films. The polyenic carboxylic acid behaves as a photoconductor, in contrast to saturated long-chain acids which act as insulators in similar experiments. The direction of the photocurrent was investigated as a function of the bias potential, as well as the concentration of QH2 and Q in the surrounding electrolyte. In the presence of a large excess of QH2 the photocurrent was anodic, but it was cathodic in the presence of a large excess of Q.

AB - Langmuir-Blodgett (LB) films of an amphipathic carotenoid, 7′-apo-7′-(4-carboxyphenyl)-β-carotene (ACC), were deposited on semiconducting transparent ITO electrodes which were then immersed in electrolyte containing benzoquinone (Q) or hydroquinone (QH2). Photocurrents were measured over the spectral range 350-700 nm. The action spectra implicate the excited carotenoid pigment, possibly in an aggregated form, as the photoactive species in the photoinduced electron transfer process. The photocurrents (up to 2 nA/cm2) were proportional to the light intensity and the number of deposited layers. The quantum yield of electron transfer was found to be independent of the number of layers, which implies efficient charge transfer between the layers. This result is unique to these carotenoid films. The polyenic carboxylic acid behaves as a photoconductor, in contrast to saturated long-chain acids which act as insulators in similar experiments. The direction of the photocurrent was investigated as a function of the bias potential, as well as the concentration of QH2 and Q in the surrounding electrolyte. In the presence of a large excess of QH2 the photocurrent was anodic, but it was cathodic in the presence of a large excess of Q.

UR - http://www.scopus.com/inward/record.url?scp=0029679146&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0029679146&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0029679146

VL - 100

SP - 814

EP - 821

JO - Journal of Physical Chemistry

JF - Journal of Physical Chemistry

SN - 0022-3654

IS - 2

ER -