Matches in SemOpenAlex for { <https://semopenalex.org/work/W2024654214> ?p ?o ?g. }
- W2024654214 endingPage "6954" @default.
- W2024654214 startingPage "6945" @default.
- W2024654214 abstract "The previously observed facile photooxidation of Ru(bpy)32+ to Ru(bpy)33+ in oxygenated solutions of 9 M H2SO4 (Kotkar, D; Joshi, V.; Ghosh, P. K. Chem. Commun. 1987, 4; Indian Patent No. 164358 (1989)) is further studied. A similar phenomenon was observed with Ru(phen)32+ but not with Ru(bpy)2[bpy-(CO2H)2]2+. The reaction is strongly dependent on acid concentration, with a sharp change in the region of 2−7 M H2SO4. The quantum yield of Ru(bpy)33+ formation in 9 M H2SO4 is close to the quantum yield of steady-state luminescence quenching by O2. Photooxidation is accompanied by near-stoichiometric formation of H2O2 as reduced product. Chromatographic, spectroscopic, electrochemical and optical rotation studies reveal that Ru(bpy)32+ survives the strongly acidic environment with little evidence of either any change in coordination sphere or ligand degradation, even after repeated cycles of photolytic oxidation followed by electrolytic reduction. The high quantum yield and selectivity of the reaction is ascribed to (i) predominance of the electron transfer quenching pathway over all others and (ii) highly efficient trapping of O2•- by H+ followed by rapid disproportionation to H2O2 and O2. These are likely on account of the high ionic strength of the medium which favors the required shifts in the potentials of the O2/O2•- and O2/H2O2 couples. Upon storage of the photooxidized Ru(III) solution in dark, partial recovery of Ru(bpy)32+ occurs gradually. Studies with the electrooxidized complex over a range of acid concentrations indicate that Ru(bpy)32+ is regenerated by reaction of Ru(bpy)33+ with H2O2. The reaction is promoted by increasing concentrations of [H2O2] and inhibited by [O2] and [H+]. The fraction of Ru(III) remaining after the reverse reaction is allowed to plateau in solutions of varying acid concentrations follows a similar trend to that found after attainment of steady state in the photooxidation reaction, although in all cases the forward reaction produces more Ru(III) than what remains in the reverse reaction. These observations are consistent with the following equation 2Ru(bpy)32+ + O2 + 2H+ →(hν)/←(dark) 2Ru(bpy)33+ + H2O2 for which the equilibrium constant has been computed. Light helps overcome the activation barrier of the forward reaction by driving it via *Ru(bpy)32+, and to the extent that the photooxidation is driven past the equilibrium, there is conversion of light energy in the form of long-lived chemical products. Spectroscopic evidence rules out any significant shift in the redox potential of Ru(bpy)33+/2+, suggesting thereby that H2O2 is much more stable in the more strongly acidic medium and less capable of reducing Ru(bpy)33+ unlike at higher pH." @default.
- W2024654214 created "2016-06-24" @default.
- W2024654214 creator A5002679033 @default.
- W2024654214 creator A5017391319 @default.
- W2024654214 creator A5039558155 @default.
- W2024654214 creator A5044324132 @default.
- W2024654214 creator A5055285229 @default.
- W2024654214 creator A5061425161 @default.
- W2024654214 creator A5074444194 @default.
- W2024654214 date "2001-06-23" @default.
- W2024654214 modified "2023-09-23" @default.
- W2024654214 title "Understanding the Facile Photooxidation of Ru(bpy)<sub>3</sub><sup>2+</sup> in Strongly Acidic Aqueous Solution Containing Dissolved Oxygen" @default.
- W2024654214 cites W141356951 @default.
- W2024654214 cites W1526682151 @default.
- W2024654214 cites W1965726476 @default.
- W2024654214 cites W1970278219 @default.
- W2024654214 cites W1970393749 @default.
- W2024654214 cites W1970656716 @default.
- W2024654214 cites W1971071471 @default.
- W2024654214 cites W1972726115 @default.
- W2024654214 cites W1973803527 @default.
- W2024654214 cites W1977211012 @default.
- W2024654214 cites W1980533523 @default.
- W2024654214 cites W1983941758 @default.
- W2024654214 cites W1985135900 @default.
- W2024654214 cites W1986594437 @default.
- W2024654214 cites W1994282950 @default.
- W2024654214 cites W1998290514 @default.
- W2024654214 cites W2000776803 @default.
- W2024654214 cites W2002791597 @default.
- W2024654214 cites W2006695018 @default.
- W2024654214 cites W2009172246 @default.
- W2024654214 cites W2014704311 @default.
- W2024654214 cites W2018360366 @default.
- W2024654214 cites W2020708117 @default.
- W2024654214 cites W2025082013 @default.
- W2024654214 cites W2025273232 @default.
- W2024654214 cites W2031509255 @default.
- W2024654214 cites W2033397176 @default.
- W2024654214 cites W2042492216 @default.
- W2024654214 cites W2044533112 @default.
- W2024654214 cites W2047769130 @default.
- W2024654214 cites W2050843981 @default.
- W2024654214 cites W2050952238 @default.
- W2024654214 cites W2051868025 @default.
- W2024654214 cites W2052752040 @default.
- W2024654214 cites W2052787337 @default.
- W2024654214 cites W2056252763 @default.
- W2024654214 cites W2062827372 @default.
- W2024654214 cites W2064791480 @default.
- W2024654214 cites W2067792578 @default.
- W2024654214 cites W2067885031 @default.
- W2024654214 cites W2073461638 @default.
- W2024654214 cites W2074404539 @default.
- W2024654214 cites W2086357472 @default.
- W2024654214 cites W2087446785 @default.
- W2024654214 cites W2087490231 @default.
- W2024654214 cites W2091933586 @default.
- W2024654214 cites W2093644325 @default.
- W2024654214 cites W2100050744 @default.
- W2024654214 cites W2112921192 @default.
- W2024654214 cites W2136930200 @default.
- W2024654214 cites W2153839866 @default.
- W2024654214 cites W224033094 @default.
- W2024654214 cites W29179573 @default.
- W2024654214 cites W2950809643 @default.
- W2024654214 cites W2953306447 @default.
- W2024654214 cites W4213245659 @default.
- W2024654214 cites W1995153782 @default.
- W2024654214 doi "https://doi.org/10.1021/jp0039924" @default.
- W2024654214 hasPublicationYear "2001" @default.
- W2024654214 type Work @default.
- W2024654214 sameAs 2024654214 @default.
- W2024654214 citedByCount "33" @default.
- W2024654214 countsByYear W20246542142012 @default.
- W2024654214 countsByYear W20246542142013 @default.
- W2024654214 countsByYear W20246542142014 @default.
- W2024654214 countsByYear W20246542142016 @default.
- W2024654214 countsByYear W20246542142017 @default.
- W2024654214 countsByYear W20246542142018 @default.
- W2024654214 countsByYear W20246542142020 @default.
- W2024654214 countsByYear W20246542142021 @default.
- W2024654214 crossrefType "journal-article" @default.
- W2024654214 hasAuthorship W2024654214A5002679033 @default.
- W2024654214 hasAuthorship W2024654214A5017391319 @default.
- W2024654214 hasAuthorship W2024654214A5039558155 @default.
- W2024654214 hasAuthorship W2024654214A5044324132 @default.
- W2024654214 hasAuthorship W2024654214A5055285229 @default.
- W2024654214 hasAuthorship W2024654214A5061425161 @default.
- W2024654214 hasAuthorship W2024654214A5074444194 @default.
- W2024654214 hasConcept C121332964 @default.
- W2024654214 hasConcept C121745418 @default.
- W2024654214 hasConcept C123669783 @default.
- W2024654214 hasConcept C134121241 @default.
- W2024654214 hasConcept C144082473 @default.
- W2024654214 hasConcept C147789679 @default.
- W2024654214 hasConcept C161790260 @default.
- W2024654214 hasConcept C171001562 @default.