Phase evolution during formation of SrAl2O4 from SrCO3 and α-Al2O3/AlOOH

Yu Lun Chang, Hsing I. Hsiang, Ming Tsai Liang

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)

Abstract

Through the execution of experimental investigation, thermogravimetry, X-ray diffractometry, Fourier transform-infrared spectrometry, transmission electron microscopy, and energy-dispersive spectrometry, a variant reaction mechanism model was proposed for the solid-state reaction between SrCO 3 and Al2O3/AlOOH for formation of SrAl 2O4 material. The solid-state reaction is observed to be dependent on the calcination temperature. At temperatures lower than the transformation temperature of SrCO3 from orthorhombic to hexagonal (920°C), the reaction is attributed to the interfacial reaction between SrCO3 and alumina. Conversely, at temperatures higher than that, the solid-state reaction is dominated by the diffusion of Al3+ ions into the SrCO3 lattice. In this mechanism, two metastable species, hexagonal SrCO3 and hexagonal SrAl2O4, were observed. The activation energies of SrCO3 decomposition in the solid-state reaction also support these results. The interfacial reaction at low temperatures is characterized by a high activation energy of ∼130 kJ/mol; whereas, in the reaction at higher temperatures, the activation energy of SrCO3 decomposition decreases to 34 kJ/mol.

Original languageEnglish
Pages (from-to)2759-2765
Number of pages7
JournalJournal of the American Ceramic Society
Volume90
Issue number9
DOIs
Publication statusPublished - 2007 Sep

All Science Journal Classification (ASJC) codes

  • Ceramics and Composites
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Phase evolution during formation of SrAl<sub>2</sub>O<sub>4</sub> from SrCO<sub>3</sub> and α-Al<sub>2</sub>O<sub>3</sub>/AlOOH'. Together they form a unique fingerprint.

Cite this