Charge-transfer sensitizer

Molecular engineering of ruthenium complexes that can act as panchromatic charge-transfer sensitizers for TiOi-based solar cells presents a challenging task, as several requirements which are very difficult to be met simultaneously have... 

Bach et al. have successfully introduced the concept of a solid p-type semiconductor (heterojunction), with the amorphous organic hole-transport material 2,2, 7,7 -tetrakis (, V, V-di-/ -methoxyphcnyl-aminc)9,9 -spirobifluorenc [96]. This hole-conducting material allows the regeneration of the sensitizers after electron injection due to its hole-transport properties. Nevertheless, the incident photon-to-current conversion efficiencies using complex 22 as a charge-transfer sensitizer... 

Figure 9. Heterogeneous charge transfer sensitizer for molecular photovoltaic cells.

Heimer T. A. and Meyer G. J. (1996), Luminescence of charge transfer sensitizers anchored to metal oxide nanoparticles , J. Lumin. 70, 468 78. 

X2bis(2,2 -bipyridyl-4,4 -dicarboxylate)ruthenium(II) charge-transfer sensitizers (X = cr, Br , r, CIST, and SCIST) on nanocrystalline Ti02 eleetrodes , J. Am. Chem. Soc. 115, 6382-6390. 

Nazeeruddin M. K., Zakeerudin S. M., Humphry-Baker R., Jirousek M., Liska P., Vlachopoulos N., Shklover V., Fischer C.-H. and Gratzel M. (1999), Aeid-base equilibria of (2,2 -bipyridyl-4-4 -dicarboxylic acid)ruthenium(II) eomplexes and the effect of protonation on charge-transfer sensitization of nanoerystalline titania , Inorg. Chem. 38, 6298-6305. 

Many long-term tests have been performed with the N3-type ruthenium complexes confirming the extraordinary stability of these charge transfer sensitizers. For example, a European consortinm financed under the Joule program [41,42] has confirmed... 

Add-base equilibria of (2,2 -bipyridyl-4,4 -(ficarboxylic acid) ruthenium(II) complexes and the effect of protonation on charge-transfer sensitization of nanocrystaDine titania. 

M. K. Nazeeruddin, A. Kay, 1. Rodicio et al.. Conversion of light to electricity by cis-X2bis(2,2 -Bipyridyl-4,4 -Dicarboxylate) Ruthenium(li) charge-transfer sensitizers... 

Dattelbaum DM, Itokazu MK, Dia NYM et al (2003) Mechanism of metal-to-ligand charge transfer sensitization of olefin trans-to-cis isomerization in the fac-[Re (phen)(CO)3(l,2-bpe)]" cation. J Phys Chem A 107 4092-4095... 

Dye-sensitized nanocrystalline Ti02 solar cells are presently under intensive investigation. " So far, the best performing charge transfer sensitizer employed for such an application is the cw-dithiocyanato-bis(4,4 -dicarboxy-2,2 -bipyridi-ne)ruthenium(II) complex, yielding solar-to-electric power conversion efficiency of 10% under standard solar conditions. These cells exhibit a remarkable stability, making practical applications feasible. 

Acid-Base Equilibria of (2,2 -Bipyridyl-4,4 -dicarboxylic acid)ruthenium(II) Complexes and the Effect of Protonation on Charge-Transfer Sensitization of Nanocrystalline Titania. 

Grutsch, P.A. and Kutal, C., Charge-transfer sensitization of the valence isomerization of norbor-nadiene to quadricyclane by an orthometallated transition-metal complex,/. Am. Chem. Soc., 108, 3108-3110, 1986. 

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