Tris-bipyridine based dinuclear ruthenium(II)-osmium(III) complex dyads grafted onto TiO2 nanoparticles for mimicking the artificial photosynthetic Z-scheme

Ludovic Favereau, Abhinandan Makhal, David Provost, Yann Pellegrin, Errol Blart, Erik Göransson, Leif Hammarström, Fabrice Odobel

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The Z-Scheme function within molecular systems has been rarely reported for solar energy conversion although it offers the possibility to achieve higher efficiency than single photon absorber photosystems due to the use of a wider range of visible light. In this study, we synthesized and investigated the electrochemical and spectroscopic properties of two new dyads based on ruthenium and osmium tris-bipyridine complexes covalently linked via a butane bridge to explore their ability to realize the Z-scheme function once immobilized on TiO2. These dyads can be grafted onto a nanocrystalline TiO2 film via the osmium complex bearing two dicarboxylic acid bipyridine ligands, while the ruthenium complex contains either two unsubstituted bipyridine ancillary ligands (RuH-Os) or two (4,4′-bis-trifluoromethyl-bipyridine) ancillary ligands (RuCF3-Os). Transient absorption spectroscopy studies of the Ru(II)-Os(III) dyads with femtosecond and nanosecond lasers were conducted both in solution and on TiO2. For both conditions, the photophysical studies revealed that the MLCT excited state of the ruthenium complex is strongly quenched and predominantly decays by energy transfer to the LMCT of the adjacent Os(III) complex, in spite of the high driving force for electron transfer. This unexpected result, which is in sharp contrast to previously reported Ru(II)-Os(III) dyads, precluded us to achieve the expected Z-scheme function. However, the above results may be a guide for designing new artificial molecular systems reproducing the complex function of a Z-scheme with molecular systems grafted onto a TiO2 mesoporous film.

Original languageEnglish
Pages (from-to)4778-4786
Number of pages9
JournalPhysical Chemistry Chemical Physics
Volume19
Issue number6
DOIs
Publication statusPublished - 2017

Fingerprint

Osmium
Ruthenium
osmium
ruthenium
Nanoparticles
nanoparticles
Ligands
ligands
Bearings (structural)
solar energy conversion
Dicarboxylic Acids
dicarboxylic acids
butanes
Absorption spectroscopy
Energy conversion
Excited states
Energy transfer
Solar energy
absorbers
electron transfer

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this

Tris-bipyridine based dinuclear ruthenium(II)-osmium(III) complex dyads grafted onto TiO2 nanoparticles for mimicking the artificial photosynthetic Z-scheme. / Favereau, Ludovic; Makhal, Abhinandan; Provost, David; Pellegrin, Yann; Blart, Errol; Göransson, Erik; Hammarström, Leif; Odobel, Fabrice.

In: Physical Chemistry Chemical Physics, Vol. 19, No. 6, 2017, p. 4778-4786.

Research output: Contribution to journalArticle

Favereau, Ludovic ; Makhal, Abhinandan ; Provost, David ; Pellegrin, Yann ; Blart, Errol ; Göransson, Erik ; Hammarström, Leif ; Odobel, Fabrice. / Tris-bipyridine based dinuclear ruthenium(II)-osmium(III) complex dyads grafted onto TiO2 nanoparticles for mimicking the artificial photosynthetic Z-scheme. In: Physical Chemistry Chemical Physics. 2017 ; Vol. 19, No. 6. pp. 4778-4786.
@article{1429a386471a47239742f20e21027818,
title = "Tris-bipyridine based dinuclear ruthenium(II)-osmium(III) complex dyads grafted onto TiO2 nanoparticles for mimicking the artificial photosynthetic Z-scheme",
abstract = "The Z-Scheme function within molecular systems has been rarely reported for solar energy conversion although it offers the possibility to achieve higher efficiency than single photon absorber photosystems due to the use of a wider range of visible light. In this study, we synthesized and investigated the electrochemical and spectroscopic properties of two new dyads based on ruthenium and osmium tris-bipyridine complexes covalently linked via a butane bridge to explore their ability to realize the Z-scheme function once immobilized on TiO2. These dyads can be grafted onto a nanocrystalline TiO2 film via the osmium complex bearing two dicarboxylic acid bipyridine ligands, while the ruthenium complex contains either two unsubstituted bipyridine ancillary ligands (RuH-Os) or two (4,4′-bis-trifluoromethyl-bipyridine) ancillary ligands (RuCF3-Os). Transient absorption spectroscopy studies of the Ru(II)-Os(III) dyads with femtosecond and nanosecond lasers were conducted both in solution and on TiO2. For both conditions, the photophysical studies revealed that the MLCT excited state of the ruthenium complex is strongly quenched and predominantly decays by energy transfer to the LMCT of the adjacent Os(III) complex, in spite of the high driving force for electron transfer. This unexpected result, which is in sharp contrast to previously reported Ru(II)-Os(III) dyads, precluded us to achieve the expected Z-scheme function. However, the above results may be a guide for designing new artificial molecular systems reproducing the complex function of a Z-scheme with molecular systems grafted onto a TiO2 mesoporous film.",
author = "Ludovic Favereau and Abhinandan Makhal and David Provost and Yann Pellegrin and Errol Blart and Erik G{\"o}ransson and Leif Hammarstr{\"o}m and Fabrice Odobel",
year = "2017",
doi = "10.1039/c6cp06679h",
language = "English",
volume = "19",
pages = "4778--4786",
journal = "Physical Chemistry Chemical Physics",
issn = "1463-9076",
publisher = "Royal Society of Chemistry",
number = "6",

}

TY - JOUR

T1 - Tris-bipyridine based dinuclear ruthenium(II)-osmium(III) complex dyads grafted onto TiO2 nanoparticles for mimicking the artificial photosynthetic Z-scheme

AU - Favereau, Ludovic

AU - Makhal, Abhinandan

AU - Provost, David

AU - Pellegrin, Yann

AU - Blart, Errol

AU - Göransson, Erik

AU - Hammarström, Leif

AU - Odobel, Fabrice

PY - 2017

Y1 - 2017

N2 - The Z-Scheme function within molecular systems has been rarely reported for solar energy conversion although it offers the possibility to achieve higher efficiency than single photon absorber photosystems due to the use of a wider range of visible light. In this study, we synthesized and investigated the electrochemical and spectroscopic properties of two new dyads based on ruthenium and osmium tris-bipyridine complexes covalently linked via a butane bridge to explore their ability to realize the Z-scheme function once immobilized on TiO2. These dyads can be grafted onto a nanocrystalline TiO2 film via the osmium complex bearing two dicarboxylic acid bipyridine ligands, while the ruthenium complex contains either two unsubstituted bipyridine ancillary ligands (RuH-Os) or two (4,4′-bis-trifluoromethyl-bipyridine) ancillary ligands (RuCF3-Os). Transient absorption spectroscopy studies of the Ru(II)-Os(III) dyads with femtosecond and nanosecond lasers were conducted both in solution and on TiO2. For both conditions, the photophysical studies revealed that the MLCT excited state of the ruthenium complex is strongly quenched and predominantly decays by energy transfer to the LMCT of the adjacent Os(III) complex, in spite of the high driving force for electron transfer. This unexpected result, which is in sharp contrast to previously reported Ru(II)-Os(III) dyads, precluded us to achieve the expected Z-scheme function. However, the above results may be a guide for designing new artificial molecular systems reproducing the complex function of a Z-scheme with molecular systems grafted onto a TiO2 mesoporous film.

AB - The Z-Scheme function within molecular systems has been rarely reported for solar energy conversion although it offers the possibility to achieve higher efficiency than single photon absorber photosystems due to the use of a wider range of visible light. In this study, we synthesized and investigated the electrochemical and spectroscopic properties of two new dyads based on ruthenium and osmium tris-bipyridine complexes covalently linked via a butane bridge to explore their ability to realize the Z-scheme function once immobilized on TiO2. These dyads can be grafted onto a nanocrystalline TiO2 film via the osmium complex bearing two dicarboxylic acid bipyridine ligands, while the ruthenium complex contains either two unsubstituted bipyridine ancillary ligands (RuH-Os) or two (4,4′-bis-trifluoromethyl-bipyridine) ancillary ligands (RuCF3-Os). Transient absorption spectroscopy studies of the Ru(II)-Os(III) dyads with femtosecond and nanosecond lasers were conducted both in solution and on TiO2. For both conditions, the photophysical studies revealed that the MLCT excited state of the ruthenium complex is strongly quenched and predominantly decays by energy transfer to the LMCT of the adjacent Os(III) complex, in spite of the high driving force for electron transfer. This unexpected result, which is in sharp contrast to previously reported Ru(II)-Os(III) dyads, precluded us to achieve the expected Z-scheme function. However, the above results may be a guide for designing new artificial molecular systems reproducing the complex function of a Z-scheme with molecular systems grafted onto a TiO2 mesoporous film.

UR - http://www.scopus.com/inward/record.url?scp=85013498398&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85013498398&partnerID=8YFLogxK

U2 - 10.1039/c6cp06679h

DO - 10.1039/c6cp06679h

M3 - Article

AN - SCOPUS:85013498398

VL - 19

SP - 4778

EP - 4786

JO - Physical Chemistry Chemical Physics

JF - Physical Chemistry Chemical Physics

SN - 1463-9076

IS - 6

ER -