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Title: Synthesis and structure of nanocrystalline mixed Ce–Yb silicates

Abstract

Graphical abstract: - Highlights: • New method of synthesis of nanocrystalline mixed lanthanide silicates is proposed. • Formation of A-type (Ce{sub 1−y}Yb{sub y}){sub 2}Si{sub 2}O{sub 7} in well dispersed Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)}–SiO{sub 2} system. • Formation of Yb{sub y}Ce{sub 9.33−y}(SiO{sub 4}){sub 6}O{sub 2} in agglomerated Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)}–SiO{sub 2} system. - Abstract: This work presents results of studies on synthesis and structure of mixed, nanocrystalline Ce–Yb silicates. Using TEM, XRD and FTIR we showed that heat treatment of nanocrystalline Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)} (x = 0.3, 0.5) mixed oxide supported on amorphous silica in reducing atmosphere, results in formation of Ce–Yb mixed silicates. Dispersion of the oxide on the silica surface and thus a local lanthanide/Si atomic ratio determines the stoichiometry of the silicate. Oxide crystallites uniformly dispersed on the silica surface transformed into A-(Ce{sub 1−y}Yb{sub y}){sub 2}Si{sub 2}O{sub 7} disilicate, while the agglomerated nanoparticles converted into Yb{sub y}Ce{sub 9.33−y}(SiO{sub 4}){sub 6}O{sub 2} oxyapatite silicate as an intermediate phase.

Authors:
;
Publication Date:
OSTI Identifier:
22290468
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 48; Journal Issue: 7; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CRYSTALS; HEAT TREATMENTS; MICROSTRUCTURE; NANOSTRUCTURES; RARE EARTHS; SILICATES; SILICON OXIDES; SYNTHESIS; TRANSMISSION ELECTRON MICROSCOPY

Citation Formats

Małecka, Małgorzata A., E-mail: M.Malecka@int.pan.wroc.pl, and Kępiński, Leszek. Synthesis and structure of nanocrystalline mixed Ce–Yb silicates. United States: N. p., 2013. Web. doi:10.1016/J.MATERRESBULL.2013.03.008.
Małecka, Małgorzata A., E-mail: M.Malecka@int.pan.wroc.pl, & Kępiński, Leszek. Synthesis and structure of nanocrystalline mixed Ce–Yb silicates. United States. doi:10.1016/J.MATERRESBULL.2013.03.008.
Małecka, Małgorzata A., E-mail: M.Malecka@int.pan.wroc.pl, and Kępiński, Leszek. 2013. "Synthesis and structure of nanocrystalline mixed Ce–Yb silicates". United States. doi:10.1016/J.MATERRESBULL.2013.03.008.
@article{osti_22290468,
title = {Synthesis and structure of nanocrystalline mixed Ce–Yb silicates},
author = {Małecka, Małgorzata A., E-mail: M.Malecka@int.pan.wroc.pl and Kępiński, Leszek},
abstractNote = {Graphical abstract: - Highlights: • New method of synthesis of nanocrystalline mixed lanthanide silicates is proposed. • Formation of A-type (Ce{sub 1−y}Yb{sub y}){sub 2}Si{sub 2}O{sub 7} in well dispersed Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)}–SiO{sub 2} system. • Formation of Yb{sub y}Ce{sub 9.33−y}(SiO{sub 4}){sub 6}O{sub 2} in agglomerated Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)}–SiO{sub 2} system. - Abstract: This work presents results of studies on synthesis and structure of mixed, nanocrystalline Ce–Yb silicates. Using TEM, XRD and FTIR we showed that heat treatment of nanocrystalline Ce{sub 1−x}Yb{sub x}O{sub 2−(x/2)} (x = 0.3, 0.5) mixed oxide supported on amorphous silica in reducing atmosphere, results in formation of Ce–Yb mixed silicates. Dispersion of the oxide on the silica surface and thus a local lanthanide/Si atomic ratio determines the stoichiometry of the silicate. Oxide crystallites uniformly dispersed on the silica surface transformed into A-(Ce{sub 1−y}Yb{sub y}){sub 2}Si{sub 2}O{sub 7} disilicate, while the agglomerated nanoparticles converted into Yb{sub y}Ce{sub 9.33−y}(SiO{sub 4}){sub 6}O{sub 2} oxyapatite silicate as an intermediate phase.},
doi = {10.1016/J.MATERRESBULL.2013.03.008},
journal = {Materials Research Bulletin},
number = 7,
volume = 48,
place = {United States},
year = 2013,
month = 7
}
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