Ruthenium/rhenium complexes

F,MnO SC6, Manganese( I), pentacarbonyl-(trifluoromethanesulfonato)-, 26 114 F,0 CH, Acetic acid, trifluoro-tungsten complex, 26 222 F,02C,H, Acetic acid, trifluoro-ruthenium complex, 26 254 FjOjSCH, Methanesulfonic acid, trifluoro-iridium, manganese and rhenium complexes, 26 114, 115, 120 platinum complex, 26 126 F304PtSC,4H,5, Platinum(II), hydrido-(methanol)bis(triethylphosphine)-Irans-, trifluoromethanesulfonate,... 

Most photosensitizers, however, are reasonably photostable compounds, and their optical properties have been studied in depth. In particular, there has been much interest in ruthenium-based photosensitizers such as [Ru(bpy)3]2+ and [Ru(phen)3]2+, due to their stability and absorption of visible light. Detailed information on their optical properties, including ground and excited state information in relation to photosensitization, has been reviewed by Creutz et al. [16]. Similarly, the photochemistry and photophysics of rhenium complexes, as discussed here, have been reviewed in detail by Kirgan et al. [7]. 

The rhenium complexes described in Section 11.2 have also been studied as electron mediators for C02 reduction at metal electrodes. Hawecker et al. used the complex Re(bpy)(CO)3Cl in DMF/water (9 1) at glassy carbon electrodes at a potential of-1.44V (versus SCE) to produce CO with 98% faradaic efficiency [15, 87]. Likewise, Sullivan et al. reported the production of CO with similar efficiency at a platinum electrode at -1.5 V (versus SCE) by using the complex fac-Re(bpy) (CO)3Cl [88]. Ruthenium complexes that have been used in photochemical... 

Besides ruthenium complexes, rhenium complexes were also used as the photosensitizers in photovoltaic cells. Bulk heterojunction photovoltaic cells fabricated from sublimable rhenium complexes exhibited a power conversion efficiency of 1.7%.75,76 The same rhenium complex moiety was incorporated into conjugated polymer chains such as polymer 16a c (Scheme 9). Fabrication of devices based on conjugated rhenium containing polymers 17a c and SPAN by the LbL deposition method was reported.77 The efficiencies of the devices are on the order of 10 4%. 

The luminescence spectra of all receptors in CH3CN were found to be dramatically affected by the addition of acetate or chloride. While compound 19 exhibits an emission decrease, the other receptors 17,18 and 20 show a remarkable intensity increase (up to 500%) with a slight concomitant blue shift of the emission maximum (660 nm for 17). The anion-induced enhancement of luminescence intensity in the case of 17 is clearly due to the decrease of the electron transfer between the ruthenium(II) bipyridyl centre and the quinone moieties. Alternatively, receptors bearing ruthenium or rhenium complexes on the upper rim were also described [20]. 

In addition to described heterogeneous systems a homogeneous photocatalytic C02 reduction was tested using heteroleptic rhenium complexes [99, 100] and supramolecular ruthenium and rhenium bi- and tetranuclear complexes their excited states were quenched by 1-benzyl-1,4-dihydronicotinamide (BNAH) and C02 was reduced by the electron donor intermediate species [101]. 

Gholamkhass B, Mametsuka H, Koike K, Tanabe T, Furue M, Ishitani O. Architecture of supramolecular metal complexes for photocatalytic C02 reduction ruthenium-rhenium bi- and tetranuclear complexes. Inorg Chem 2005 44 2326-36. 

NaY and Al-MCM-41 encapsulated rhenium complexes Al-MCM-41 supported ruthenium complexes Rhenium complex encapsulated in NaY zeolite... 

Supramolecular photocatalysts connecting several rhenium complexes to a ruthenium complex and connecting several ruthenium complexes to one rhenimn complex have also been S5mthesized. The photocatalytic abilities toward CO2 reduction of each were RuRe2 (TNco = 190)> Ru2Re (TNco = H0) (99,100), RuRe3 ( co = 0.093, TNco = 240) (96). 

CH]Br, Methane, bromo-, osmium and ruthenium complexes, 27 201, 205 CH.i, Methyl, iridium complex, 26 118 CHj, Methyl, manganese complex, 26 156 osmium complex, 27 206 rhenium complexes, 26 107 CHiCI, Methane, chloro-, osmium complex, 27 205... 

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