ALL libraries (COBIB.SI union bibliographic/catalogue database)
  • Local environment of manganese incorporated in mesoporous MCM-41
    Novak Tušar, Nataša ...
    Manganese containing MCM-41 was synthesised by the direct hydrothermal method (DHT) in the presence of cetyltrimethylammonium chloride (CTACl) as a template. The local environment of manganese ... incorporated in mesoporous silicate MCM-41 was investigated by XAS (X-ray Absorption Spectroscopy). XANES(X-ray Absorption Near Edge Structure) studies showed the coexistence of Mn2+ and Mn3+ cations in both, as-synthesised and template-free MnMCM-41 samples. The major part of manganese cations in the as-synthesised MnMCM-41 was Mn2+, while in the template-free MnMCM-41 the amount of Mn3+ was increased. EXAFS (X-ray Absorption Fine Structure) analyses revealed that major part of manganese cations in the as-synthesised MnMCM-41 were extra-framework with the Mn-O distance of 2.19 . Manganese cations in the template-free MnMCM-41 were incorporated into the framework and coordinated tothree oxygens in the first coordination shell, with two of them at a shorterdistance of 1.92 and one at a longer distance of 2.21 . Pulsed ESR (Electron Spin Resonance) and ESEEM (Electron Spin-Echo Envelope Modulation) investigations were in agreement with the XANES and EXAFS results.
    Source: Microporous and mesoporous materials : zeolites, clays, carbons and related materials. - ISSN 1387-1811 (Vol. 82, no. 1, 2005, str. 129-136)
    Type of material - article, component part
    Publish date - 2005
    Language - english
    COBISS.SI-ID - 3265050

Shelf entry