Extinction coefficients, ruthenium

D. Kuang, C. Klein, S. Ito, et al., High-efficiency and stable mesoscopic dye-sensitized solar cells based on a high molar extinction coefficient ruthenium sensitizer and nonvolatile electrolyte, Advanced Materials, vol. 19, no. 8, 1133 pages, 2007. 

Kuang D, Ito S, Wenger B, Klein C, Moser JE, Baker RH, Zakeeruddin SM, Gratzel M (2006). High molar extinction coefficient heteroleptic ruthenium complxes for thin-film dye sensitized solar cells. J Am Chem Soc 128 4146-4154... 

Osmium(II) and ruthenium(II) complexes are strongly absorbing species. Their extinction coefficients are in the range (5—11) x 103 M-1 cm-1 around 500 nm. The corresponding complexes in the oxidation state 3+ absorb visible light much weaker and therefore the GO-catalyzed oxidation of D-glucose by Os111 complexes, which obeys stoichiometric Eq. (43), can be monitored spectrophotometrically as in the case of ferricenium salts. 

The cell is on the verge of commercialization, offering a potential alternative for the currently used silicon-based photovoltaic devices.12 An unprecedented conversion efficiency of 11% could be manufactured from relatively cheap materials.19 The most up-to-date efficient DSSCs are based on ruthenium complexes. Several representative ruthenium sensitizers possess high extinction coefficient and high photovoltaic performance are shown in Scheme 1.15-19... 

Dyes such as erythrosin B [172], eosin [173-177], rose bengal [178,179], rhodamines [180-185], cresyl violet [186-191], thionine [192], chlorophyll a and b [193-198], chlorophyllin [197,199], anthracene-9-carboxylate [200,201], perylene [202,203] 8-hydroxyquinoline [204], porphyrins [205], phthalocyanines [206,207], transition metal cyanides [208,209], Ru(bpy)32+ and its analogs [83,170,210-218], cyanines [169,219-226], squaraines [55,227-230], and phe-nylfluorone [231] which have high extinction coefficients in the visible, are often employed to extend the photoresponse of the semiconductor in photoelectro-chemical systems. Visible light sensitization of platinized Ti02 photocatalyst by surface-coated polymers derivatized with ruthenium tris(bipyridyl) complex has also been attempted [232,233]. Because the singlet excited state of these dyes is short lived it becomes essential to adsorb them on the semiconductor surface with... 

Ruthenium and osmium polyazine complexes have been widely used as light absorbers. The complex [Ru(bpy)3] (Fig. 2) is a well studied LA with high extinction coefficients in the ultraviolet and visible regions of the spectrum. This complex shows intense absorptions in the UV region that are intraligand n- n (IL) and in the visible region that are MLCT transitions. Upon optical excitation at 450 nm, population of the Ru(d7i)- bpy(ji ) MLCT occurs. 

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