89980-97-2Relevant articles and documents
Effects of the Polyelectrolyte Poly(vinyl sulfate) on the Photosensitized Electron-Transfer Reactions of Tris(2,2'-bipyridine)ruthenium(II) with a Dipolar Zwitterionic Viologen
Sassoon, Richard E.,Aizenshtat, Ze'ev,Rabani, Joseph
, p. 1182 - 1190 (1985)
The photosensitized electron-transfer system containing Ru(bpy)32+ as photosensitizer and N,N'-bis(4-sulfonatotolyl)-4,4'-bipyridyldiylium (BSV) as quencher was investigated in aqueous solutions containing the polyelectrolyte poly(vinyl sulfate) (PVS).This is the first system where acceleration of the forward quenching reaction together with considerable retardation of the reaction regenerating the ground-state species occurs on addition of a charged microenvironment.Both the BSV molecule, possessing a large dipole moment, and the Ru(bpy)32+ cation are concentrated in the polyelectrolyte field and steady-state emission experiments showed that the distribution of BSV in the potential field of PVS may be described by the Poisson-Boltzmann equation.The reaction between BSV and Ru(bpy)32+ results in an electron transfer, yielding BSV-. and Ru(bpy)33+ as products.There is evidence for formation of an outer-sphere complex between BSV-. and Ru(bpy)33+.The yields of electron transfer were hardly affected by the presence of PVS although the rate of the reverse electron-transfer reaction was somewhat reduced.This was attributed to the distribution of charge over the BSV-. radical anion product.The effects of pH, addition of an inert salt, and variation of coverage of the polyelectolyte were also investigated for the system.
Visible light-induced hole injection into rectifying molecular wires anchored on Co3O4 and SiO2 nanoparticles
Soo, Han Sen,Agiral, Anil,Bachmeier, Andreas,Frei, Heinz
, p. 17104 - 17116 (2013/01/15)
Tight control of charge transport from a visible light sensitizer to a metal oxide nanoparticle catalyst for water oxidation is a critical requirement for developing efficient artificial photosynthetic systems. By utilizing covalently anchored molecular w
Synthesis and characterization of water-soluble phenylene-vinylene-based singlet oxygen sensitizers for two-photon excitation
Nielsen, Christian B.,Johnsen, Mette,Arnbjerg, Jacob,Pittelkow, Michael,McIlroy, Sean P.,Ogilby, Peter R.,Jorgensen, Mikkel
, p. 7065 - 7079 (2007/10/03)
The synthesis and characterization of water-soluble singlet oxygen sensitizers with a phenylene-vinylene motif is presented. The principal motivation for this study was to better understand specific features of a water-soluble molecule that influence the photosensitized production of singlet oxygen upon nonlinear, two-photon excitation of that molecule. To achieve water solubility, sensitizers were synthesized with ionic as well as nonionic substituents. In the ionic approach, salts of N-methylated pyridine, benzothiazole, and 1-methyl-piperazine moieties were used, as were aryl-substituted sulfonic acid moieties. In the nonionic approach, aryl-substituted triethylene glycol moieties were used. Selected photophysical properties of the compounds synthesized were determined, including singlet oxygen quantum yields. Of the molecules examined, the most efficient singlet oxygen sensitizers had triethylene glycol units as the functional group that imparted water solubility. Molecules containing the ionic moieties did not make singlet oxygen in appreciable yield nor did they efficiently fluoresce. Rather, for these latter molecules, rapid charge-transfer-mediated nonradiative processes appear to dominate excited state deactivation.
