Abstract
Calcium stannate (Ca 2SnO 4) nanoparticles with an average size of about 15 nm were synthesized via single-step mechanochemical processing of binary oxide precursors at room temperature. High-resolution TEM studies revealed a nonuniform structure of mechanosynthesized Ca 2SnO 4 nanoparticles consisting of an ordered core surrounded by a disordered surface shell region. The inner core of a Ca 2SnO 4nanoparticle possesses a fully ordered orthorhombic structure, and the surface shell exhibits the thickness of about 1.5 nm. The volume fraction of surface shell regions in the nanostructured mechanosynthesized stannate is estimated to be about 50%. Because of the ability of both solid-state 119Sn MAS NMR and 119Sn Mössbauer spectroscopies to probe the local environment of Sn nuclei, valuable complementary insight into the local structural disorder in mechanosynthesized Ca 2SnO 4 was obtained. It was concluded that the near-surface layers of stannate nanoparticles are disordered because of broadly distorted geometry of SnO 6 octahedra. The octahedra are deformed in such a way that they become more regular.
Original language | English |
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Pages (from-to) | 2518-2524 |
Number of pages | 7 |
Journal | Chemistry of Materials |
Volume | 21 |
Issue number | 12 |
DOIs | |
Publication status | Published - 2009 Jun 23 |
ASJC Scopus subject areas
- Chemistry(all)
- Chemical Engineering(all)
- Materials Chemistry