14302-87-5Relevant articles and documents
Russell, A. S.,Evans, D. C.,Rowell, S. W.
, (1926)
Electron-Transfer Quenching of Ruthenium(II) Photosensitizers by Mercury(II) in Aqueous Nitrate Media
Hauenstein, B. L.,Dressick, W. J.,Demas, J. N.,DeGraff, B. A.
, p. 2418 - 2422 (1984)
Excited-state interactions of tris(α-diimine)ruthenium(II) photosensitizers with Hg2+ were studied in aqueous nitrate media by using luminescence qyenching and flash photolysis methods.Quenching proceeds via oxidative electron transfer to yield Ru(III) and a Hg(I) free radical with high effenciency.Regardless of the excited-state reducing power of the photosensitizer, quenching was near but below the Marcus diffusion-controlled limit.Dimerization of the Hg(I) free radical to give Hg22+ competes effectively with the diffusion-limited back-electron-transfer reaction of the free radical with the Ru(III) species.The back-reaction rate of Hg22+ and Ru(III) is much slower and depends on E0(Ru(III/II)).The efficiency of electron-transferred-product separation is sensitive to E0(Ru(III/II)).The mechanism of the oxidation of Hg22+ by Ru(III) is discussed.
Mechanistic study of quinoliniumdichromate (QDC) oxidation of mercury(I) in aqueous sulfuric acid in the presence of micro amounts of palladium(II) - Autocatalysis in catalysis
Chimatadar,Basavaraj,Nandibewoor
, p. 2976 - 2984 (2006)
The kinetics of oxidation of mercury(I) with quinoliniumdichromate (QDC) in the presence of micro amounts of palladium(II) catalyst in aqueous sulfuric acid medium has been studied under varying conditions. The active species of oxidant, reductant and catalyst in the reaction medium were understood to be HCrO4-, [Hg2(SO4)HSO4]- and PdCl+, respectively. The autocatalysis by one of the products, chromium(III), was observed. A composite scheme and rate law were proposed. Reaction constants involved in the mechanism have been evaluated.
Visible light assisted photodegradation of thimerosal by high performance ZnFe2O4/poly(o-phenylenediamine) composite
Sandoval, Claudio,Ranganathan, Suresh,Ramírez, Eimmy,Mansilla, Héctor D.,Dinamarca, Robinson,Pecchi, Gina,Yá?ez, Jorge
, p. 8 - 15 (2019)
Thimerosal is a mercury-based preservative that is used in pharmaceuticals, vaccines and health-care products. However, thimerosal toxicity has been well explored and hence it should be properly treated for avoiding its occurrence in the environment. Hence, we synthesized visible light active ZnFe2O4/poly(o-phenylenediamine) composite as photocatalyst for degradation of thimerosal. The well characterized ZnFe2O4 and composite effectively degraded thimerosal and subsequently reduced Hg(II) into Hg(0) under visible light irradiation. Thimerosal degradation by-products and generation of Hg(0) were analyzed by high performance liquid chromatography and atomic fluorescence spectroscopy. The composite showed better photocatalytic activity than the pure ZnFe2O4 nanoparticles. Under the optimum conditions, 90.2% degradation of thimerosal was achieved within 6 h of irradiation. An efficient charge separation ability of poly(o-phenylenediamine) contributes to the high photocatalytic performance of the composite. This work provides a new photocatalytic degradation pathway of thimerosal and thus will stimulate further studies in the removal of organometallic contaminants.
Phases of underpotentially deposited Hg on Au(111): An in situ surface X-ray diffraction study
Li, Jun,Abru?a, Héctor D.
, p. 2907 - 2916 (1997)
We report on an in situ surface X-ray diffraction study of the underpotential deposition (UPD) of mercury on Au(111). We have observed three UPD phases present at potentials prior to bulk mercury deposition. These phases consist of two well-ordered intermediate states and what appears to be either a fully discharged two-dimensional liquid Hg layer or a monolayer of an amorphous Hg-Au alloy. Both ordered intermediate phases have hexagonal structures with lattice vectors that are rotated 30° from those of the Au(111) substrate. The first phase (phase I), present at a potential of +0.68 V, was only observed on fresh flame-annealed Au(111) electrodes and appears to be an open incommensurate structure with a lattice constant of 3.86 ± 0.03 A?. This phase appears to be metastable since it changes to a second ordered phase (phase II) after a certain time at +0.68 V or after the potential is moved to more negative values (+0.63 V). The second phase has a more compact lattice with a = 3.34 ± 0.01 A? and appears to be a commensurate 2×2 structure with 2/3 of the Hg atoms at threefold hollow sites and 1/3 on atop sites. Similar to the first one, this phase is also metastable and can be transformed to a final, fully discharged, state of a two-dimensional liquid Hg layer or an amorphous Hg-Au alloy. The entire Hg UPD process, from Hg2+ to the fully discharged metallic Hg layer, agrees well with a multistep mechanism based on previous electrochemical kinetic studies on polycrystalline Au electrodes. Our results also show that the UPD of Hg on Au(111) electrodes is quite different from that of other metals such as Cu, Ag, Tl, and Pb.
Photodisproportionation of Hg22+
Kunkely, Horst,Vogler, Arnd
, p. 375 - 377 (2002)
The photolysis of Hg2+2 in tetrahydrofuran induced by metal-metal σσ* excitation leads to the generation of Hg0 and Hg2+. The quantum yield of this photodisproportionation is ? = 0.03 at λirr = 254 nm
