Synthesis and microstructural characterization of nano-size calcium phosphates with different stoichiometry

Date

2011-04-01

Author

Ergun, Celaletdin
Evis, Zafer
Webster, Thomas J.
Sahin, Filiz Cinar

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

201
views

0
downloads

Calcium phosphates with Ca/P molar ratios of 0.5, 0.75, 1.33, 1.5, 1.55, 1.67, 2.0, and 2.5 were synthesized by a wet chemistry precipitation method and sintered at 500 degrees C, 700 degrees C, 900 degrees C, 1100 degrees C and 1300 degrees C for 2 h. Presence of phases and microstructures of calcium phosphates were determined by X-ray diffraction and scanning electron microscopy. In all different Ca/P ratios, the precipitated phase was always hydroxyapatite with very small size and/or partial disorderness regardless of the Ca/P ratios in the starting precipitating medium. For samples with 0.5 and 0.75 Ca/P ratios in starting solution, tricalcium phosphate and calcium pyrophosphate phases were observed. In contrast, for samples with 1.0 and 1.33 Ca/P ratios, the only stable phase was tricalcium phosphate. For the samples with Ca/P ratio of 1.5, the tricalcium phosphate phase was dominant. However, small amounts of hydroxyapatite started to appear. For samples with Ca/P ratio of 1.67, the hydroxyapatite phase was dominant. Lastly, for samples with the Ca/P ratios of 2.0 and 2.5, the CaO phase started to appear in addition to the hydroxyapatite phase which was the dominant phase. Moreover, the average grain size, porosity (%) and the average pore size decreased with increasing the Ca/P ratios. (c) 2010 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Subject Keywords

Process Chemistry and Technology, Materials Chemistry, Electronic, Optical and Magnetic Materials, Surfaces, Coatings and Films, Ceramics and Composites

URI

https://hdl.handle.net/11511/42470

Journal

CERAMICS INTERNATIONAL

DOI

https://doi.org/10.1016/j.ceramint.2010.11.004

Collections

Department of Engineering Sciences, Article

Suggestions

OpenMETU
Core

Silver and fluoride doped hydroxyapatites: Investigation by microstructure, mechanical and antibacterial properties Turkoz, Mustafa; Atilla, Aykan Onur; Evis, Zafer (Elsevier BV, 2013-12-01) Hydroxyapatite co-doped with Ag+ and F- ions was synthesized by the precipitation method and sintered at 1100 degrees C for 1 h. Samples were characterized by density, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and scanning electron microscopy to investigate their microstructure, phase formation and bonding characteristics. Moreover, samples were also characterized by microhardness and antibacterial tests. Small amount of dopings resulted in high densities and fine grain...
Synthesis and characterization of poly(allyl methacrylate) obtained by free radical initiator Vardareli, Tugba Kantav; Keskin, Selda; Usanmaz, Ali (Informa UK Limited, 2008-01-01) Allyl methacrylate was polymerized in CCl4 solution by alpha,alpha'-azoisobutyronitrile at 50, 60, and 70 degrees C. The kinetic curves were auto-accelarated types at 60 and 70 degrees C, but almost linear at 50 degrees C. Arrhenius activation energy was 77.5 kJ/mol. The polymer was insoluble in common organic solvents. It was characterized by FT-IR, NMR, DSC, TGA and XPS methods. About 98-99% of allyl side groups were remained as pendant even after completion of the polymerization. The spectroscopic and th...
Effect of YF3 on the phase stability and sinterability of hydroxyapatite-Partially stabilized zirconia composites Aykul, Anil; KUTBAY, IŞIL; Evis, Zafer; USTA, Metin (Elsevier BV, 2013-09-01) Pure hydroxyapatite (HA), HA and partially stabilized zirconia composites (PSZ) with YF3 and HA-PSZ composite containing 5 wt% PSZ without YF3 were sintered in air at 900 degrees C, 1100 degrees C and 1300 degrees C for 1 h. The reactions and transformation of the phases in the composites were determined by X-ray diffraction. All the composites with or without YF3 showed desirable thermal stability below 1300 degrees C and besides various amounts of CaZrO3, any amount of tri-calcium phosphate (TCP) was not ...
Morphology and magnetic properties of barium hexaferrite ceramics synthesized in x wt% NaCl-(100-x) wt% KCL molten salts Aydogan, Eda; Kaya, Serap; Dericioğlu, Arcan Fehmi (Elsevier BV, 2014-01-01) Micron size barium hexaferrite (BaFe12O19) platelets were prepared by the molten-salt synthesis method in various weight proportions of NaCl-KCl salt mixtures as a liquid medium. The effect of molten salt composition-x wt% NaCl and (100-x) wt% KCl-on the amount of barium hexaferrite phase formation, as well as, on the morphology and magnetic properties of the final products are discussed. Inductively coupled plasma-mass spectroscopy (ICP-MS) was used to determine the solubility of the starting materials in ...
Synthesis of a new orthorhombic metastable form of CdS through solid-state reactions Bi̇lgi̇n, M.; Kızılyallı, Meral; Usanmaz, Ali (Elsevier BV, 1989-5) CdS has been prepared through solid-gas reactions of CdO with a sulfidizing gas mixture, at 750°C for 3 hr, and slow cooling under nitrogen atmosphere. The X-ray diffraction data of the product was indexed in a hexagonal system with unit cell parameters of a = 4.136 and c = 6.713Å, which agreed with the literature data. However, the presence of extra strong lines in the X-ray diffraction pattern and the splitting in the d-spacings showed that a new orthorhombic form of CdS was obtained. The unit cell dimens...

Citation Formats

C. Ergun, Z. Evis, T. J. Webster, and F. C. Sahin, “Synthesis and microstructural characterization of nano-size calcium phosphates with different stoichiometry,” CERAMICS INTERNATIONAL, pp. 971–977, 2011, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42470.