Synthesis and photophysical properties of ruthenium(II) charge transfer sensitizers containing 4,4′-dicarboxy-2,2′-biquinoline and 5,8-dicarboxy-6,7-dihydro-dibenzo[1,10]-phenanthroline

Islam, Ashraful; Sugihara, Hideki; Singh, Latika; Hara, Kohjiro; Katoh, Ryuzi; Nagawa, Yoshinobu; Yanagida, Masatoshi; Takahashi, Yoshiaki; Murata, Shigeo; Arakawa, Hironori

doi:10.1016/s0020-1693(01)00548-5

Cited by 42 publications

(42 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Dye‐sensitized solar cells (DSSCs) based on polypyridyl Ru (II) complexes have received considerable interest in industry and academia due to their exceptional photophysical and unique and strong charge transfer (MLCT) properties, low cost production and high efficiency . DSSCs were first demonstrated by O'Regan and Grätzel in 1991 .…”

Section: Introductionmentioning

confidence: 99%

Structure–property relationship of hetero‐aromatic‐electron‐donor antennas of polypyridyl Ru (II) complexes for high efficiency dye‐sensitized solar cells

El‐Shafei

Hussain

Islam

et al. 2013

Progress in Photovoltaics

Self Cite

View full text Add to dashboard Cite

Three novel heteroleptic amphiphilic polypyridyl Ru‐complexes, coded MH08–10, with hetero‐aromatic electron‐donor ancillary ligands containing N‐benzylcarbazole (MH08), dibenzofurane (MH09) and benzothiophene moieties (MH10) were synthesized to study the influence of different heterocyclic electron donors on the interrelationship of photophysical and electrochemical properties, and device performances for dye‐sensitized solar cells (DSSCs). MH08 showed a remarkably high molar extinction coefficient of 27,650 M−1cm−1. MH08–TBA was synthesized from MH08 by converted one COOH group into −COO−+N(C4H9)4 to investigate the effect of deprotonating one carboxylic group on the Fermi level and electron injection. When compared under the same experimental device conditions using 0.3M t‐butylpyridine (TBP), the short‐circuit photocurrent density (JSC) and total conversion efficiency (%η) of MH08–10 were MH08>MH09>MH10. The differences in %η and JSC of MH08–10 were ascribed to the conjugation length coupled with the electron donation and hole‐transport strength of the ancillary ligands, which were in the following order N‐benzylcarbazole>dibenzofurane>benzothiophene. Moreover, MH08–TBA showed JSC of 19.56 mAcm−2 and %η of 9.76% compared to 17.16 mAcm−2 and 9.12% of the benchmark dye N719. The superior performance of MH08–TBA was attributed to its better light harvesting and enhanced incident‐photon‐to‐current efficiency (IPCE) conversion. DFT/TD‐DFT calculations utilizing the energy functional B3LYP and the full‐electron basis set DGDZVP were performed to calculate HOMO and LUMO energies, vertical electronic excitations, lowest singlet‐singlet electronic transitions (E0‐0), and excited state oxidation potentials. Excellent agreement was found between the experimental results and calculated data. Copyright © 2013 John Wiley & Sons, Ltd.

show abstract

Section: Introductionmentioning

confidence: 99%

Structure–property relationship of hetero‐aromatic‐electron‐donor antennas of polypyridyl Ru (II) complexes for high efficiency dye‐sensitized solar cells

El‐Shafei

Hussain

Islam

et al. 2013

Progress in Photovoltaics

Self Cite

View full text Add to dashboard Cite

show abstract

“…In the protonated and unprotonated forms, the maximum of the strong long‐wavelength 1 MLCT absorption band between 450 and 650 nm is redshifted with increasing/decreasing π‐donor/acceptor character of the ancillary ligand (bpy→NCS − →Cl − , Figure 1 and Table 1). This effect, which has been reported for related systems,5n, o, 6a, c—i, 15b, 18 relates to variations in the ligand field strength, and this results in changes in the relative energies of the d donor levels of the metal and the π* acceptor levels of the ligand involved in the 1 MLCT transitions. Interaction with π‐donor/acceptor ligands raises/lowers the energies of the donor orbitals, which results in a bathochromic/hypsochromic shift of the 1 MLCT transitions.…”

Section: Resultsmentioning

confidence: 65%

“…There are two possibilities to tune the properties and electronic character of MLCT states: 1) Tuning of the relative energies of the π* acceptor orbitals contributing to the configuration of the excited states by, for example, ligand substitution5e, m, o, p, 6d, 13 and/or protonation 5n. o, 14 2) Modifying the properties and relative energies of the d donor orbitals through coordination of ancillary ligands with varying π‐donor/acceptor character 5m–p.…”

Section: Introductionmentioning

confidence: 99%

Utilizing Ancillary Ligands to Optimize the Photophysical Properties of 4H‐Imidazole Ruthenium Dyes

Wächtler¹,

Maiuri²,

Brida³

et al. 2013

ChemPhysChem

View full text Add to dashboard Cite

Correlations between structural features and photophysical properties offer the possibility to design dyes with tailor-made properties. In this respect, the photophysical properties of a series of 4H-imidazole (4H-im) ruthenium dyes with varying chemical and electronic structures of the complex fragments [(tpy)Ru(4H-im)X] {tpy=4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine; X=Cl(-), NCS(-)} and [(bpy)2Ru(4H-im)](+) {bpy=4,4'-di-tert-butyl-2,2'-bipyridine} were investigated. Variation of the π-donor/acceptor properties of the ancillary ligands offers the possibility to tune the relative energies of the d donor and π* acceptor orbitals of 4H-im, which results in a shift in the Ru→4H-im (1)MLCT (MLCT=metal-to-ligand charge transfer) absorption band in the visible range. Further, the energies of the excited states and also the interactions and mixing of the metal d orbital with the π* 4H-im orbital are sensitive to the chemical and electronic structures of the complex fragment. This causes subtle changes in the photoinduced processes; for example, the rate of the interim population of a planarized state increases with increasing/decreasing π-acceptor/donor character of the ancillary ligand. Although ground-state repopulation in the tpy species follows the energy-gap law, local symmetry-related effects have to be considered to account for the very short lifetime of the excitation in the bpy complex. Additionally, the ultrafast intramolecular relaxation processes leading from the initially excited states to the relaxed triplet states localized on the 4H-im ligand (internal conversion, internal vibrational energy redistribution, intersystem crossing) depend on the nature of the complex fragment. The high excitation-wavelength-dependent rate for the population of the relaxed triplet states in the bpy complex points to additional interligand electron-transfer contributions upon excitation into the higher lying Ru→bpy (1)MLCT states.

show abstract

“…However, while there have been many, many publications on extending the p-system through conjugation of aromatic systems, 1 there have been relatively few that work by expanding the aromatic system. 2 Those few attempts have shown very promising results in the shift in the absorption spectrum, however, the overall efficiency was quite low. In our work, we attempted to create a new ligand for Ru-based DSSCs, using an extended aromatic system with a backbone of 5,8-dimethyl-dibenzo[b,j ] [1,10] (Figure 1) is a challenging compound to synthesize.…”

Section: Introductionmentioning

confidence: 99%

Conversion of 2,3,8,9-dibenzo-4,7-Dimethyl-5,6-dihydro-1,10 phenanthroline to Dibenzo[b,j][1,10]phenanthrolines

Ji¹,

Johnson²

2018

MOJBOC

View full text Add to dashboard Cite

In this paper, we investigated and explained the low conversion efficiency of 2,3,8,9-dibenzo-4,7-Dimethyl-5,6-dihydro-1,10-phenanthroline (2) to 5,8-dimethyl-Dibenzo[b,j][1,10] phenanthrolines (1) and the reactivity of the 1. Chemistry from similar systems predicted a generally unreactive system, with any reactivity centered at the heteroaromatic rings. Several oxidized products from 2 were also reported.

show abstract

Synthesis and photophysical properties of ruthenium(II) charge transfer sensitizers containing 4,4′-dicarboxy-2,2′-biquinoline and 5,8-dicarboxy-6,7-dihydro-dibenzo[1,10]-phenanthroline

Cited by 42 publications

References 29 publications

Structure–property relationship of hetero‐aromatic‐electron‐donor antennas of polypyridyl Ru (II) complexes for high efficiency dye‐sensitized solar cells

Structure–property relationship of hetero‐aromatic‐electron‐donor antennas of polypyridyl Ru (II) complexes for high efficiency dye‐sensitized solar cells

Utilizing Ancillary Ligands to Optimize the Photophysical Properties of 4H‐Imidazole Ruthenium Dyes

Conversion of 2,3,8,9-dibenzo-4,7-Dimethyl-5,6-dihydro-1,10 phenanthroline to Dibenzo[b,j][1,10]phenanthrolines

Contact Info

Product

Resources

About