In situ evolution of Ni environment in magnesium aluminosilicate glasses and glass–ceramics–Influence of ZrO2 and TiO2 nucleating agents. (March 2015)

• Record Type: Journal Article
• Authors: Dugué, A.; Dymshits, O.; Cormier, L.; Cochain, B.; Lelong, G.; Zhilin, A.; Belin, S.
• Is Part Of: Journal of physics and chemistry of solids. Volume 78(2015:Mar.)
• Page Start: 137
• Page End: 146
• Publication Date: 2015-03
• Subjects: Glasses -- Crystal growth -- XAFS (EXAFS and XANES) -- X-ray diffraction -- Optical properties; Solids -- Periodicals; Solides -- Périodiques; Solids; Periodicals; 530.41
• DOI: 10.1016/j.jpcs.2014.11.008
• Languages: English
• ISSNs: 0022-3697

Abstract

Abstract: The evolution of Ni 2+ environment has been systematically investigated using optical and in situ X-ray absorption spectroscopy (XAS) to determine the influence of nucleating agents (TiO2 and/or ZrO2 ) during the formation of spinel in magnesium aluminosilicate glass–ceramics. The results were complemented by in situ X-ray diffraction data. According to XAS and optical spectroscopy, the nature of nucleating agents does not modify significantly the Ni environment in initial glasses. However, it has a relatively strong influence in the observed crystallization sequence. Ni 2+ ions do not enter the Zr-containing crystalline phase of ZrO2 or ZrTiO4 but a Ni 2+ coordination change from the fivefold coordinated sites, with a small amount of tetrahedral sites in parent glasses, to [6] Ni 2+ and [4] Ni 2+ sites in spinel (in glasses nucleated by ZrO2 and/or TiO2 ) or in β-quartz solid solutions (in glasses nucleated by ZrO2 ) has been found.