Kinetics of electron-transfer cross-reactions within redox polymers. Coatings of a protonated polylysine copolymer with incorporated electroactive anions

The kinetics of the outer-sphere electron transfer reactions of tris(1,1′-dioxo-2,2′-bipyridine)cobalt(II) and (III) with a series of nickel polyaza macrocycles, FeL3n+ and OsL32+ complexes (L is 2,2′-bipyridine or 1,10-phenanthroline, and substituted derivatives), and Rh2(O2CCH3)4(CH3CN)2+ have been investigated in acetonitrile at 25.0 °C. An application of the Marcus theory relationship to the cross-reaction rate constants yielded apparent Co(bpyO2)32+/3+ self-exchange rate constants of 102 M−1 s−1 from the nickel macrocycle cross-reactions and 10−1 M−1 s−1 from the cross-reactions with the metal polypyridine complexes. The latter cross-reactions are considered to be non-adiabatic due to a mismatch in the donor/acceptor orbital symmetries. The electron exchange rate constant is compared with the exchange rate constants for other Co(II)/Co(III) complex couples and M(bpyO2)32+/3+ couples of other first-row transition metals, and discussed in terms of inner-sphere and solvent reorganization barriers. Keywords: electron transfer, Marcus theory relationship, cobalt(II)/(III) couples, 1,1′-dioxo-2,2′-bipyridine.

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The Analysis of Solvent Effects on the Kinetics of Simple Heterogeneous Electron Transfer Reactions

10.21236/ada210078 ◽

1988 ◽

Author(s):

W. R. Fawcett ◽

Jr Foss ◽

C. A.

Keyword(s):

Electron Transfer ◽

Solvent Effects ◽

Transfer Reactions ◽

Electron Transfer Reactions ◽

Heterogeneous Electron Transfer ◽

Kinetics Of

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ChemInform Abstract: KINETICS OF ELECTRON TRANSFER BETWEEN VITAMIN B12 COMPOUNDS

Chemischer Informationsdienst ◽

10.1002/chin.197803376 ◽

1978 ◽

Vol 9 (3) ◽

Author(s):

E. J. KAUFMANN ◽

J. H. ESPENSON

Keyword(s):

Electron Transfer ◽

Vitamin B12 ◽

Kinetics Of

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Single entity electrochemistry and the electron transfer kinetics of hydrazine oxidation

Nano Research ◽

10.1007/s12274-021-3353-8 ◽

2021 ◽

Cited By ~ 1

Author(s):

Ruiyang Miao ◽

Lidong Shao ◽

Richard G. Compton

Keyword(s):

Electron Transfer ◽

Bulk Solution ◽

Relative Contribution ◽

Rate Determining Step ◽

Multistep Process ◽

Ph Range ◽

Electro Catalytic Oxidation ◽

Single Particle Impact ◽

The Impact ◽

Kinetics Of

AbstractThe mechanism and kinetics of the electro-catalytic oxidation of hydrazine by graphene oxide platelets randomly decorated with palladium nanoparticles are deduced using single particle impact electrochemical measurements in buffered aqueous solutions across the pH range 2–11. Both hydrazine, N2H4, and protonated hydrazine N2H5+ are shown to be electroactive following Butler-Volmer kinetics, of which the relative contribution is strongly pH-dependent. The negligible interconversion between N2H4 and N2H5+ due to the sufficiently short timescale of the impact voltammetry, allows the analysis of the two electron transfer rates from impact signals thus reflecting the composition of the bulk solution at the pH in question. In this way the rate determining step in the oxidation of each specie is deduced to be a one electron step in which no protons are released and so likely corresponds to the initial formation of a very short-lived radical cation either in solution or adsorbed on the platelet. Overall the work establishes a generic method for the elucidation of the rate determining electron transfer in a multistep process free from any complexity imposed by preceding or following chemical reactions which occur on the timescale of conventional voltammetry.

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