Ruthenium 2,2 -bipyridyl complexes

The dye sensitised semi-conductor electrode is a transparent conducting sheet of glass coated (5 pm) with nanocrystalline TiOj (diameter 20 nm) doped with a ruthenium bipyridyl complex. The dye absorbs light, becomes excited and injects electrons into the TiOj electrode. The electrons travel into the transparent WO3 hhn and then, to balance the charge, lithium ions from the electrolyte solution insert into the WO3 and in so doing create the coloured species as described above. If the light source is removed then the cell is bleached back to its original colour. However, if the... 

Other workers have employed different sensitiser systems, e.g. duel sensitisation by a zinc porphyrin and copper phthalocyanine on TiOj, Eosin Y or tetrabro-mophenol blue on ZnO, and a ZnO/SnOj mixture with a ruthenium bipyridyl complex, to produce good energy conversion factors. 

Ruthenium bipyridyl complexes are suitable photosensitizers because then-excited states have a long lifetime and the oxidized Ru(III) center has a longterm chemical stability. Therefore, Ru bipyridyl complexes have been studied intensively as photosensitizers for homogeneous photocatalytic reactions and dye-sensitization systems. The Ru bipyridyl complex, bis(2,2 -bipyridine)(2,2 -bipyri-dine-4, 4,-dicarboxylate)ruthenium(II), having carboxyl groups as anchors to the semiconductor surface was synthesized and single-crystal Ti02 photoelectrodes sensitized by this Ru complex were studied in 1979 and 1980 [5,6]. 

The use of transition or rare earth metal complexes as emitting materials for OLED has attracted much attention recently because of the enhancement in EL efficiency from triplet excited state.16 Chan and co-workers demonstrated that incorporation of ruthenium bipyridyl complexes into conjugated polymers would enhance the charge carrier mobilities.17 Through attachment of different transition metal complexes onto polymer chains, tuning of light-emitting properties could be achieved.18... 

PHOTO-INDUCED ELECTRON TRANSFER REACTIONS IN POLYMER-BOUND RUTHENIUM BIPYRIDYL COMPLEXES... 

Visible light soaking alone is not a dominant stress factor, which means that the dye (a ruthenium bipyridyl complex) used in these tests is surprisingly stable [7,18,19]. 

Tennakone K., Kumara G. R. R., Kottegoda I. R. M., Wijayantha K. G. U. and Perera V. P. S. (1998). A solid-state photo voltaic cell sensitized with a ruthenium bipyridyl complex , /. Phys. D Appl. Phys. 31, 1492-1496. 

Photocurrent generation is one of the most interesting direct applications of photosynthetic studies. The adsorption of sensitizers onto semiconductor surfaces has been found to be an efficient way to generate photocurrents and has been studied extensively. Ruthenium bipyridyl complexes, in particular, have been the focus of recent research [137-139]. In these cases, only the first layer of molecules, which is in direct contact with the surface, is active. A highly porous semiconductor material was therefore employed to compensate for the low level of absorption of the single molecular layer. Other varieties of chromophores, semiconductor materials, and electron carriers for totally solid systems have been the subjects of extensive studies. The present... 

For coordinating and sensing luminescent lanthanide ions, a luminescent ruthenium bipyridyl complex has been covalently linked to one, two or six lower rim acid-amide modified caUx[4]arene moieties in receptors 155-157. All these complexes coordinated with lanthanide ions, Nd , Eu and Tb, with the formation of adducts of variable stoichiometries. The adduct formation affected the Ru luminescence, which was strongly quenched by Nd ion, increased by the Tb ion and moderately quenched or increased by Eu ion (2004IC3965). 

Professor Wang, Dr Jia and Dr Li have written about the Electro-chemiluminesence of a set of particular Ruthenium (bipyridyl) complexes. Dr Viswanatha and Dr Pandey have described the study of semiconducting quantum dots using optical spectroscopy in both frequency and time domains. 

A photoactive metal center is introduced in these systems. The ruthenium bipyridyl complexes are coordinated to the emeraldine base to form the corresponding polymer complexes as described above." The incorporation of the ruthenium centers to the pyridyl backbone has been also reported to give the ruthenium complexes Conjugated ruthenium bipyridine complexes thus obtained are evaluated to be photorefractive materials. Other transition metal complexes can be employed to form the corresponding polymer complexes. The pyridine unit is replaced by bithienyl, 1,4-diazabutadiene, ethylene, benzimidazole or thiazole. ... 

The ruthenium bipyridyl complex can be also used as a scaffold. The ruthe-nium(II) complex 18 bearing the phenylenediamine moieties has been designed and synthesized. Chemical oxidation leads to the complex 19 bearing the quinonediimine moieties (Scheme 3.9). An efficient photoinduced intramolecular electron transfer is observed with 18. 

As chemists have become more sophisticated in their ability to design and understand chemical oscillators, and as they have increasingly sought systems that are relevant to biological processes, oscillatoiy systems with feedback have become an area of growing interest. We describe here experiments (13) and computer simulations (14) on a photosensitive variant of the BZ reaction, in which the catalyst is a ruthenium bipyridyl complex, Ru(bpy)3 (15). 

Schiffinann F, VandeVondele J, Hutter J, Wirz R, Urakawa A, Baiker A (2010) Protonation-dependent binding of ruthenium bipyridyl complexes to the anatase(lOl) surface. J Phys ChemC 114(18) 8398-8404... 

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