Photocatalytic water oxidation by a mixed-valent Mn(III)3Mn(IV)O3 manganese oxo core that mimics the natural oxygen-evolving center.
Angew Chem Int Ed Engl
; 53(42): 11182-5, 2014 Oct 13.
Article
em En
| MEDLINE
| ID: mdl-25066304
ABSTRACT
The functional core of oxygenic photosynthesis is in charge of catalytic water oxidation by a multi-redox Mn(III)/Mn(IV) manifold that evolves through five electronic states (S(i), where i=0-4). The synthetic model system of this catalytic cycle and of its S0âS4 intermediates is the expected turning point for artificial photosynthesis. The tetramanganese-substituted tungstosilicate [Mn(III)3Mn(IV)O3(CH3COO)3(A-α-SiW9O34)](6-)(Mn4POM) offers an unprecedented mimicry of the natural system in its reduced S0 state; it features a hybrid organic-inorganic coordination sphere and is anchored on a polyoxotungstate. Evidence for its photosynthetic properties when combined with [Ru(bpy)3](2+) and S2O8(2-) is obtained by nanosecond laser flash photolysis; its S0âS1 transition within milliseconds and multiple-hole-accumulating properties were studied. Photocatalytic oxygen evolution is achieved in a buffered medium (pHâ
5) with a quantum efficiency of 1.7%.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxigênio
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Água
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Compostos de Tungstênio
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Compostos de Manganês
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Manganês
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2014
Tipo de documento:
Article