Features of Hydrogen Reduction of Fe(CN)63− Ions in Aqueous Solutions: Effect of Hydrogen Dissolved in Palladium Nanoparticles

Preliminary saturation of 2.6 nm palladium nanoparticles with hydrogen accelerates the reduction of Fe(CN)63− ions in aqueous solution three to four-fold. An analytical equation was derived describing the hydrogen saturation of palladium nanoparticles and the dependence of their catalytic activity on the hydrogen content in the metal. The specific rate constants of reduction do not depend on the content of palladium nanoparticles in the solution. A change in the temperature and pH or stirring of the solution do not affect the rate of catalytic reaction. Approaches to optimization of palladium-catalyzed reactions involving hydrogen are substantiated.

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Ligand substitution reactions of pentacyanoferrate(II) complexes with N-heterocyclic cations in aqueous solution

Canadian Journal of Chemistry ◽

10.1139/v89-274 ◽

1989 ◽

Vol 67 (11) ◽

pp. 1774-1779 ◽

Cited By ~ 7

Author(s):

Donal Hugh Macartney ◽

Lauren Jean Warrack

Keyword(s):

Aqueous Solution ◽

Rate Constants ◽

Dissociation Constants ◽

Formation Rate ◽

Spectroscopic Studies ◽

Ligand Substitution ◽

Acid Dissociation ◽

Specific Rate ◽

Dissociative Mechanism ◽

Heterocyclic Cations

Kinetic and spectroscopic studies have been carried out in aqueous solution on the formation (from Fe(CN)5OH23−) and dissociation of pentacyanoferrate(II) complexes containing 1-(4-pyridyl)pyridinium and the neutral, protonated, and N-methylated forms of 4,4′-bipyridine (BPY), 1,2-bis(4-pyridyl)ethane (BPA), and trans-1,2-bis(4-pyridyl)ethylene (BPE). The pH dependences of the formation kinetics have been analyzed in terms of the specific rate and acid dissociation constants for these ligands. The rate constants (25.0 °C, I = 0.10 M) for the formation of the dinuclear complexes (NC)5FeLFe(CN)56− have been determined for BPY (50 M−1 s−1), BPA (66 M−1 s−1), BPE (95 M−1 s−1), and pyrazine (10 M−1 s−1), and are compared with the respective rate constants for the formation of (NC)5FeLCo(NH3)5. The relationships between the formation rate constants and the size of the ligand, the number of donor sites, and the magnitude and position of charges on the ligand are discussed in terms of an ion-pair dissociative mechanism. Keywords: pentacyanoferrate(II) complexes, N-heterocycles, ligand substitution, kinetics.

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Palladium nanoparticles in aqueous solution: Preparation, properties, and effect of their size on catalytic activity

Colloid Journal ◽

10.1134/s1061933x14040048 ◽

2014 ◽

Vol 76 (5) ◽

pp. 553-557 ◽

Cited By ~ 3

Author(s):

B. G. Ershov ◽

R. D. Solovov ◽

E. V. Abkhalimov

Keyword(s):

Aqueous Solution ◽

Catalytic Activity ◽

Palladium Nanoparticles ◽

Solution Preparation

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Facile Interpretation of Catalytic Reaction between Organic Dye Pollutants and Silver Nanoparticles with Different Shapes

Journal of Nanomaterials ◽

10.1155/2019/3257892 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Ja Young Cheon ◽

Su Jun Kim ◽

Won Ho Park

Keyword(s):

Aqueous Solution ◽

Silver Nanoparticles ◽

Catalytic Activity ◽

Zeta Potential ◽

Catalytic Reaction ◽

Organic Dye ◽

Crystalline Form ◽

Ag Nps ◽

Dye Pollutants ◽

Different Shapes

In this study, various shapes of silver nanoparticles (Ag NPs) were synthesized via simple methods in aqueous solution. The size and shape of Ag NPs were measured by TEM image and DLS, and the crystalline form of Ag NPs was confirmed by XRD. From ATR-IR and zeta potential, the Ag NPs were found to be well surrounded by PVP. In addition, the catalytic activity of Ag NPs was evaluated using model dyes. Unlike the conventional catalysts, the model dyes with absorption peaks that did not overlap with the SPR peaks of the Ag NPs were selected to evaluate the catalytic activity without removal of the Ag NPs from the dye solution.

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Decomposition of hydrogen peroxide on a two-component NiO-CdO catalyst and the effect of ionizing radiation on its catalytic properties

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19791015 ◽

1979 ◽

Vol 44 (4) ◽

pp. 1015-1022 ◽

Cited By ~ 7

Author(s):

Viliam Múčka

Keyword(s):

Aqueous Solution ◽

Hydrogen Peroxide ◽

Catalytic Activity ◽

Nickel Oxide ◽

Catalytic Properties ◽

Cadmium Oxide ◽

Chemisorb Oxygen ◽

Composition Region ◽

Chemisorbed Oxygen ◽

Two Component

The catalytic properties of two-component catalyst nickel oxide-cadmium oxide with the proportions of the components covering the whole composition region 0-100% were examined by studying the decomposition of hydrogen peroxide in aqueous solution on it. In the range 0-25 mol.% CdO, cadmium oxide is found to affect infavourably the ability of nickel oxide to chemisorb oxygen. The amount of the chemisorbed oxygen increases several times on gamma irradiation of the samples. The effect of cadmium oxide on the catalytic activity of the system shows up in fresh samples only indirectly via the changed amount of the oxygen chemisorbed. In older samples the initial catalytic activity of the system is changed, which can be explained based on the concept of bivalent catalytic centres in terms of the co-action of the catalytic centres of the two oxides, which are in equilibrium. The irradiation of the system under study speeds up the processes leading to the establishing of this equilibrium which is thermally very stable, and results in a substantial increase of the catalytic activity of the samples investigated.

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