Mechanical Alloying and Thermal Decomposition of (ZrO2)0.8–(α-Fe2O3)0.2 Powder for Gas Sensing Applications

✍ Scribed by W. Cao; O.K. Tan; W. Zhu; B. Jiang

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 213 KB
• Volume: 155
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8920

✦ Synopsis

The mechanical alloying process of (ZrO 2 ) 0.8 +( -Fe 2 O 3 ) 0.2 powder during high-energy ball milling at room temperature and the thermal decomposition of (ZrO 2 ) 0.8 +( -Fe 2 O 3 ) 0.2 powder at high temperature were studied by XRD, TEM, and di4erential thermal analysis. It was found that monoclinic zirconia transforms to cubic zirconia stabilized by Fe 3؉ after a milling time of 60 h. With the increased milling time up to 120 h, the powder appeared to consist of amorphous-like conglomerates. This metastable compound decomposed at a temperature of 6503C. The expulsion of the -Fe 2 O 3 from the cubic ZrO 2 correlated directly with the current conductivity behavior and the oxygen gas sensing property of the thick 5lm devices screen printed from this powder. The substitutional model Fe 2 O 3 {2Fe Zr ؉V G ؉3O 0 was adapted to explain both the mechanical alloying and thermal decomposition processes.