• Medientyp: E-Artikel
  • Titel: Mechanochemical Processing of Mn and Co Oxides: An Alternative Way to Synthesize Mixed Spinels for Protective Coating
  • Beteiligte: Masi, Andrea; Bellusci, Mariangela; Carlini, Maurizio; McPhail, Stephen J.; Padella, Franco; Reale, Priscilla
  • Erschienen: Wiley, 2016
  • Erschienen in: Journal of the American Ceramic Society
  • Sprache: Englisch
  • DOI: 10.1111/jace.13863
  • ISSN: 0002-7820; 1551-2916
  • Schlagwörter: Materials Chemistry ; Ceramics and Composites
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  • Beschreibung: <jats:p>High‐Energy Ball Milling (<jats:styled-content style="fixed-case">HEBM</jats:styled-content>) is proposed as a cost effective and environmental friendly technique to produce Co‐ and Mn‐ based oxides suitable for application as protective coating. Mixtures of manganese and cobalt oxides in different molar ratio (Co:Mn = 1:1 and Co:Mn = 2:1) were subjected to mechanochemical treatment up to 100 h and morpho‐structural evolution was evaluated. <jats:styled-content style="fixed-case">XRD</jats:styled-content> analysis results show that the <jats:styled-content style="fixed-case">HEBM</jats:styled-content> treatment promotes the solid‐state reaction of the starting compounds, with the formation of different crystalline phases when compared to high‐temperature solid‐state synthesis. <jats:styled-content style="fixed-case">SEM</jats:styled-content> obs<jats:italic>erv</jats:italic>ations and N<jats:sub>2</jats:sub> adsorption measurements suggest that all processed powders are composed by <jats:italic>aggregates</jats:italic> of nanometric particles. While long milling time is required to complete the reaction, 10 hours are enough to activate the powders to obtain the desired phases after a mild thermal treatment, as evidenced by <jats:italic>in situ</jats:italic> thermal <jats:styled-content style="fixed-case">XRD</jats:styled-content> analysis. Electrical conductivity measures performed with the Van der Pauw method on sintered pellets evidence a significant difference between the two compositions, related to the dual‐phase nature of Co:Mn = 1:1 material at intermediate temperatures (i.e., <jats:italic>T</jats:italic> &lt; 700°C), Co:Mn = 2:1 sample showing higher conductivity values in the whole tested range (500°C–800°C).</jats:p>