Synthesis and crystal structure characterization of silicate apatite Sr2Y8(SiO4)6O2
Tok, Alfred Iing Yoong
Date of Issue2010
School of Materials Science and Engineering
Pure Sr2Y8(SiO4)6O2 powders were obtained after a solid-state reaction at 1400 °C for 6 h using the nanosized Y2O3, commercial SrCO3, and silica gel. The nanosized Y2O3 powder was synthesized by a precipitation method using Y(NO3)3 and NH4HCO3, followed by a heat treatment. The crystal structure of Sr2Y8(SiO4)6O2 was characterized by powder X-ray diffraction, Rietveld refinement, and high-resolution transmission electron microscopy. Results show that Sr2Y8(SiO4)6O2 has a typical apatite-type structure AI4AII6(BO4)6X2 in the P63/m space group. The lattice parameters are a=9.3884(6) Å and c=6.8657(4) Å. There are two special sites, AI (4f) and AII (6h), in the apatite structure. The AII sites are fully occupied by Y, while the AI sites are randomly filled by Y and Sr atoms. The crystallographic data obtained from Sr2Y8(SiO4)6O2 and other silicate oxyapatites are compared and summarized.
Journal of the American ceramic society
© 2010 The American Ceramic Society. This is the author created version of a work that has been peer reviewed and accepted for publication by Journal of the American Ceramic Society, The American Ceramic Society. It incorporates referee’s comments but changes resulting from the publishing process, such as copyediting, structural formatting, may not be reflected in this document. The published version is available at: [http://dx.doi.org/10.1111/j.1551-2916.2009.03563.x].