TU Darmstadt / ULB / TUbiblio

Thermodynamic Control of Phase Composition and Crystallization of Metal-Modified Silicon Oxycarbides

Ionescu, E. and Terzioglu, C. and Linck, C. and Kaspar, J. and Navrotsky, A. and Riedel, R. and Gauckler, L. (2013):
Thermodynamic Control of Phase Composition and Crystallization of Metal-Modified Silicon Oxycarbides.
In: Journal of the American Ceramic Society, 96 (6), Wiley-VCH Verlag GmbH & Co. KGaA, pp. 1899-1903, ISSN 00027820,
[Online-Edition: http://dx.doi.org/10.1111/jace.12327],
[Article]

Abstract

Silicon oxycarbides modified with main group or transition metals (SiMOC) are usually synthesized via pyrolysis of sol-gel precursors from suitable metal-modified orthosilicates or polysiloxanes. In this study, the phase composition of different SiMOC systems (M = Sn, Fe, Mn, V, and Lu) was investigated. Depending on the metal, different ceramic phases formed. For M = Mn and Lu, MOx/SiOC ceramic nanocomposites were formed, whereas other compositions revealed the formation of M/SiOC (M = Sn), MSix/SiOC (M = Fe) or MCx/SiOC (M = V) upon pyrolysis. The different phase compositions of the SiMOC materials are rationalized by a simple thermodynamic approach which generally correctly predicts which type of ceramic nanocomposite is expected upon ceramization of the metal-modified precursors. Calculations show that the thermodynamic stability of the MOx phase with respect to that of the C–O system is the most important factor to predict phase formation in polymer-derived SiMOC ceramic systems. A secondary factor is the relative stability of metal oxides, silicates, carbides, and silicides.

Item Type: Article
Erschienen: 2013
Creators: Ionescu, E. and Terzioglu, C. and Linck, C. and Kaspar, J. and Navrotsky, A. and Riedel, R. and Gauckler, L.
Title: Thermodynamic Control of Phase Composition and Crystallization of Metal-Modified Silicon Oxycarbides
Language: English
Abstract:

Silicon oxycarbides modified with main group or transition metals (SiMOC) are usually synthesized via pyrolysis of sol-gel precursors from suitable metal-modified orthosilicates or polysiloxanes. In this study, the phase composition of different SiMOC systems (M = Sn, Fe, Mn, V, and Lu) was investigated. Depending on the metal, different ceramic phases formed. For M = Mn and Lu, MOx/SiOC ceramic nanocomposites were formed, whereas other compositions revealed the formation of M/SiOC (M = Sn), MSix/SiOC (M = Fe) or MCx/SiOC (M = V) upon pyrolysis. The different phase compositions of the SiMOC materials are rationalized by a simple thermodynamic approach which generally correctly predicts which type of ceramic nanocomposite is expected upon ceramization of the metal-modified precursors. Calculations show that the thermodynamic stability of the MOx phase with respect to that of the C–O system is the most important factor to predict phase formation in polymer-derived SiMOC ceramic systems. A secondary factor is the relative stability of metal oxides, silicates, carbides, and silicides.

Journal or Publication Title: Journal of the American Ceramic Society
Volume: 96
Number: 6
Publisher: Wiley-VCH Verlag GmbH & Co. KGaA
Divisions: 11 Department of Materials and Earth Sciences > Material Science > Dispersive Solids
11 Department of Materials and Earth Sciences > Material Science
11 Department of Materials and Earth Sciences
Date Deposited: 19 Feb 2014 13:15
Official URL: http://dx.doi.org/10.1111/jace.12327
Identification Number: doi:10.1111/jace.12327
Funders: Funded by German Research Foundation. Grant Numbers: IO-64/1, IO-64/3., Funded by Materials World Network. Grant Number: NSF MWN-0906070.
Export:
Suche nach Titel in: TUfind oder in Google
Send an inquiry Send an inquiry

Options (only for editors)

View Item View Item