Effect of calcination on nanoscale zirconia produced by high temperature hydrolysis

Autor:	Abdul Quddus, Anwar Ul-Hamid, H. Saricimen
Rok vydání:	2015
Předmět:	Materials science Organic Chemistry Metals and Alloys Analytical chemistry Mineralogy Surfaces Coatings and Films Baddeleyite law.invention Field emission microscopy Crystallinity law Specific surface area Materials Chemistry Cubic zirconia Calcination Crystallite Monoclinic crystal system
Zdroj:	Protection of Metals and Physical Chemistry of Surfaces. 51:803-811
ISSN:	2070-206X 2070-2051
DOI:	10.1134/s2070205115050214
Popis:	Acidic and ammoniacal zirconium chloride solutions were subjected to high temperature hydrolysis (HTH) at temperatures between 110 and 150°C. The precipitates obtained from ammoniacal solutions were identified as monoclinic zirconia of Baddeleyite type as dried at room temperature (RT). Their lattice parameters varied between 5.004 and 5.493 Angstrom (A), and crystallite size between 0.99 and 1.58 nm. The BET specific surface area of the dry powder was measured between 144 and 183 m2/g, corresponding to the equivalent particle diameter of 6.94 and 5.37 nm, respectively. Analysis carried out using field emission scanning electron microscope (FESEM) indicated that the size of zirconia particles ranged between 20 and 220 nm. Calcination of zirconia precipitates at 800°C for 2 hours (h) in air increased the crystallinity and crystal size of the precipitate, and affected the monoclinic crystal structure. It was also observed that the monoclinic crystal structure partially transformed into cubic and tetragonal zirconia.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::90ae865548557103a3c6a96f5de9a755 https://doi.org/10.1134/s2070205115050214 Zobrazit plný text záznamu Full text from SpringerLink