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Ru^III(edta) complexes as molecular redox catalysts in chemical and electrochemical reduction of dioxygen and hydrogen peroxide: inner-sphere versus outer-sphere mechanism.

ABSTRACT: The reduction of molecular oxygen (O₂) and hydrogen peroxide (H₂O₂) by [Ru^II(edta)(pz)]^2- (edta^4- = ethylenediaminetetraacetate; pz = pyrazine) has been studied spectrophotometrically and kinetically in aqueous solution. Exposure of the aqua-analogue [Ru^II(edta)(H₂O)]^2- to O₂ and H₂O₂ resulted in the formation of [Ru^III(edta)(H₂O)]^- species, with subsequent formation of the corresponding Ru^V[double bond, length as m-dash]O complex. A working mechanism for the O₂ and H₂O₂ reduction reactions mediated by the Ru^II(edta) complexes is proposed. The role of the coordinated water molecule (by its absence or presence in the primary coordination sphere) in controlling the mechanistic pathways, outer-sphere or inner-sphere, is discussed.

SUBMITTER: Chatterjee D

PROVIDER: S-EPMC9034107 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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RuIII(edta) complexes as molecular redox catalysts in chemical and electrochemical reduction of dioxygen and hydrogen peroxide: inner-sphere versus outer-sphere mechanism.

Chatterjee Debabrata D Chrzanowska Marta M Katafias Anna A Oszajca Maria M van Eldik Rudi R

RSC advances 20210616 35

The reduction of molecular oxygen (O2) and hydrogen peroxide (H2O2) by [RuII(edta)(pz)]2- (edta4- = ethylenediaminetetraacetate; pz = pyrazine) has been studied spectrophotometrically and kinetically in aqueous solution. Exposure of the aqua-analogue [RuII(edta)(H2O)]2- to O2 and H2O2 resulted in the formation of [RuIII(edta)(H2O)]- ...[more]

PMID: 35478799

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