Phase transformation in cordierite gel synthesized by non-hydrolytic sol–gel route
2006; Elsevier BV; Volume: 33; Issue: 7 Linguagem: Inglês
10.1016/j.ceramint.2006.05.003
ISSN1873-3956
AutoresIvona Janković‐Častvan, Slavica Lazarević, D. Tanasković, Aleksandar Orlović, Rada Petrović, Djordje Janaćković,
Tópico(s)X-ray Diffraction in Crystallography
ResumoCordierite gel was synthesized by non-hydrolytic sol–gel route, starting from aluminum chloride, TEOS and magnesium chloride dissolved in absolute ethanol. Crystallization of μ-cordierite from gel at temperatures between 900 and 1000 °C was confirmed by differential thermal analyses, X-ray and FTIR spectroscopy. Higher calcination temperature resulted in the transformation of μ- to α-cordierite. The value of Avrami parameter n = 2.23 for the μ-cordierite crystallization indicates contribution of different simultaneous mechanisms: homogeneous nucleation and three-dimensional crystallite growth due to homogeneity of gel and surface crystallization due to submicron particles of the gel.
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