A biomimetic approach to artificial photosynthesis: Ru(II)-polypyridine photo-sensitisers linked to tyrosine and manganese electron donors

L. Hammarström, L. Sun, B. Åkermark, S. Styring

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

The paper describes recent advances towards the construction of functional mimics of the oxygen evolving complex in photosystem II (PSII) that are coupled to photoinduced charge separation. Some key principles of PSII and artificial systems for light-induced charge accumulation are discussed. Systems are described where biomimetic electron donors - manganese complexes and tyrosine - have been linked to a Ru(II)-polypyridine photosensitiser. Oxidation of the donors by intramolecular electron transfer from the photo-oxidised Ru(III) complex has been studied using optical flash photolysis and EPR experiments. A step-wise electron transfer Mn2(III,III) → tyrosine → Ru(III) has been demonstrated, in analogy to the reaction on the donor side of PSII. Electron transfer from the tyrosine to Ru(III) was coupled to tyrosine deprotonation. This resulted in a large reorganisation energy and thus a slow reaction rate, unless the tyrosine was hydrogen bonded or already deprotonated. A comparison with analogous reactions in PSII is made. Finally, light-induced oxidation of a manganese dimer linked to a Ru(II)-photosensitiser has been observed. Preliminary results suggest the possibility of photo-oxidising manganese dimers in several steps, which is an important advancement towards water oxidation.

Original languageEnglish
Pages (from-to)2145-2160
Number of pages16
JournalSpectrochimica Acta - Part A Molecular and Biomolecular Spectroscopy
Volume57
Issue number11
DOIs
Publication statusPublished - Sep 14 2001

Fingerprint

photosynthesis
Photosynthesis
tyrosine
biomimetics
Biomimetics
Manganese
Photosystem II Protein Complex
Tyrosine
manganese
Photosensitizers
Electrons
electron transfer
Photosensitizing Agents
Dimers
Oxidation
electrons
oxidation
Deprotonation
dimers
Photolysis

Keywords

  • Artificial photosynthesis
  • Electron transfer
  • Manganese
  • Photochemistry
  • Photosystem II
  • Ruthenium

ASJC Scopus subject areas

  • Spectroscopy

Cite this

@article{5c77b3e763a14727a3babe1aee62b14c,
title = "A biomimetic approach to artificial photosynthesis: Ru(II)-polypyridine photo-sensitisers linked to tyrosine and manganese electron donors",
abstract = "The paper describes recent advances towards the construction of functional mimics of the oxygen evolving complex in photosystem II (PSII) that are coupled to photoinduced charge separation. Some key principles of PSII and artificial systems for light-induced charge accumulation are discussed. Systems are described where biomimetic electron donors - manganese complexes and tyrosine - have been linked to a Ru(II)-polypyridine photosensitiser. Oxidation of the donors by intramolecular electron transfer from the photo-oxidised Ru(III) complex has been studied using optical flash photolysis and EPR experiments. A step-wise electron transfer Mn2(III,III) → tyrosine → Ru(III) has been demonstrated, in analogy to the reaction on the donor side of PSII. Electron transfer from the tyrosine to Ru(III) was coupled to tyrosine deprotonation. This resulted in a large reorganisation energy and thus a slow reaction rate, unless the tyrosine was hydrogen bonded or already deprotonated. A comparison with analogous reactions in PSII is made. Finally, light-induced oxidation of a manganese dimer linked to a Ru(II)-photosensitiser has been observed. Preliminary results suggest the possibility of photo-oxidising manganese dimers in several steps, which is an important advancement towards water oxidation.",
keywords = "Artificial photosynthesis, Electron transfer, Manganese, Photochemistry, Photosystem II, Ruthenium",
author = "L. Hammarstr{\"o}m and L. Sun and B. {\AA}kermark and S. Styring",
year = "2001",
month = "9",
day = "14",
doi = "10.1016/S1386-1425(01)00491-7",
language = "English",
volume = "57",
pages = "2145--2160",
journal = "Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy",
issn = "1386-1425",
publisher = "Elsevier",
number = "11",

}

TY - JOUR

T1 - A biomimetic approach to artificial photosynthesis

T2 - Ru(II)-polypyridine photo-sensitisers linked to tyrosine and manganese electron donors

AU - Hammarström, L.

AU - Sun, L.

AU - Åkermark, B.

AU - Styring, S.

PY - 2001/9/14

Y1 - 2001/9/14

N2 - The paper describes recent advances towards the construction of functional mimics of the oxygen evolving complex in photosystem II (PSII) that are coupled to photoinduced charge separation. Some key principles of PSII and artificial systems for light-induced charge accumulation are discussed. Systems are described where biomimetic electron donors - manganese complexes and tyrosine - have been linked to a Ru(II)-polypyridine photosensitiser. Oxidation of the donors by intramolecular electron transfer from the photo-oxidised Ru(III) complex has been studied using optical flash photolysis and EPR experiments. A step-wise electron transfer Mn2(III,III) → tyrosine → Ru(III) has been demonstrated, in analogy to the reaction on the donor side of PSII. Electron transfer from the tyrosine to Ru(III) was coupled to tyrosine deprotonation. This resulted in a large reorganisation energy and thus a slow reaction rate, unless the tyrosine was hydrogen bonded or already deprotonated. A comparison with analogous reactions in PSII is made. Finally, light-induced oxidation of a manganese dimer linked to a Ru(II)-photosensitiser has been observed. Preliminary results suggest the possibility of photo-oxidising manganese dimers in several steps, which is an important advancement towards water oxidation.

AB - The paper describes recent advances towards the construction of functional mimics of the oxygen evolving complex in photosystem II (PSII) that are coupled to photoinduced charge separation. Some key principles of PSII and artificial systems for light-induced charge accumulation are discussed. Systems are described where biomimetic electron donors - manganese complexes and tyrosine - have been linked to a Ru(II)-polypyridine photosensitiser. Oxidation of the donors by intramolecular electron transfer from the photo-oxidised Ru(III) complex has been studied using optical flash photolysis and EPR experiments. A step-wise electron transfer Mn2(III,III) → tyrosine → Ru(III) has been demonstrated, in analogy to the reaction on the donor side of PSII. Electron transfer from the tyrosine to Ru(III) was coupled to tyrosine deprotonation. This resulted in a large reorganisation energy and thus a slow reaction rate, unless the tyrosine was hydrogen bonded or already deprotonated. A comparison with analogous reactions in PSII is made. Finally, light-induced oxidation of a manganese dimer linked to a Ru(II)-photosensitiser has been observed. Preliminary results suggest the possibility of photo-oxidising manganese dimers in several steps, which is an important advancement towards water oxidation.

KW - Artificial photosynthesis

KW - Electron transfer

KW - Manganese

KW - Photochemistry

KW - Photosystem II

KW - Ruthenium

UR - http://www.scopus.com/inward/record.url?scp=0035860113&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0035860113&partnerID=8YFLogxK

U2 - 10.1016/S1386-1425(01)00491-7

DO - 10.1016/S1386-1425(01)00491-7

M3 - Article

C2 - 11603836

AN - SCOPUS:0035860113

VL - 57

SP - 2145

EP - 2160

JO - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

JF - Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy

SN - 1386-1425

IS - 11

ER -