Polyoxometalate (POM) cluster anions are shown to serve as covalently coordinated ligands for anatase-TiO2 nanocrystals, giving isolable assemblies uniquely positioned between molecular macroanions and traditional colloidal nanoparticles. Na+ salts of the water-soluble polyanionic structures are obtained by reacting amorphous TiO2 with the 1 nm lacunary ion, Na-7[alpha-XW11O39] (X = P5+), at 170 degrees C, after which an average of 55 alpha-PW11O39-7 clusters are found as pentadentate ligands for Ti-IV ions covalently linked to 6 nm single-crystal anatase cores. The attached POMs are reversible electron acceptors, the reduction potentials of which shift in a predictable fashion by changing the central heteroatom, X, directly influencing a model catalytic reaction. Just as POM cluster anions control the reactivities of metal centers in molecular complexes, directly coordinated POM ligands with tunable redox potentials now provide new options for rationally controlling the reactions of semiconductor nanocrystals.

Polyoxometalate Complexes of Anatase-Titanium Dioxide Cores in Water

CHIEROTTI, Michele Remo;GOBETTO, Roberto;
2015-01-01

Abstract

Polyoxometalate (POM) cluster anions are shown to serve as covalently coordinated ligands for anatase-TiO2 nanocrystals, giving isolable assemblies uniquely positioned between molecular macroanions and traditional colloidal nanoparticles. Na+ salts of the water-soluble polyanionic structures are obtained by reacting amorphous TiO2 with the 1 nm lacunary ion, Na-7[alpha-XW11O39] (X = P5+), at 170 degrees C, after which an average of 55 alpha-PW11O39-7 clusters are found as pentadentate ligands for Ti-IV ions covalently linked to 6 nm single-crystal anatase cores. The attached POMs are reversible electron acceptors, the reduction potentials of which shift in a predictable fashion by changing the central heteroatom, X, directly influencing a model catalytic reaction. Just as POM cluster anions control the reactivities of metal centers in molecular complexes, directly coordinated POM ligands with tunable redox potentials now provide new options for rationally controlling the reactions of semiconductor nanocrystals.
2015
54
42
12416
12421
http://onlinelibrary.wiley.com/journal/10.1002/(ISSN)1521-3773
electron transfer; hybrid materials; nanostructures; polyoxometalates; titanium dioxide; Chemistry (all); Catalysis
Raula, Manoj; Ganor, Gal; Saganovich, Marina; Zeiri, Offer; Wang, Yifeng; Chierotti, Michele R.; Gobetto, Roberto; Weinstock, Ira A.
File in questo prodotto:
File Dimensione Formato  
angew chem int ed2015, 54, 12416-completo.pdf

Accesso riservato

Descrizione: Articolo completo
Tipo di file: PDF EDITORIALE
Dimensione 4.18 MB
Formato Adobe PDF
4.18 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
versione sottomessa.pdf

Accesso aperto

Descrizione: main text open access
Tipo di file: POSTPRINT (VERSIONE FINALE DELL’AUTORE)
Dimensione 511.74 kB
Formato Adobe PDF
511.74 kB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2318/1557685
Citazioni
  • ???jsp.display-item.citation.pmc??? 6
  • Scopus 38
  • ???jsp.display-item.citation.isi??? 34
social impact