Synthesis and characterization of thermally stable hydroxyapatite

Abstract

Nanocrystalline and thermally stable hydroxyapatite (HA) powder with nominal composition of Ca10(PO4)6(OH)2 was prepared by wet chemical route from calcium hydroxide Ca(OH)6 and mono ammonium phosphate NH4H2PO4 as calcium and phosphate sources, respectively. The effect of calcination temperature on the structure, microstructure, molecular bonding, thermal behavior and morphology was investigated by X-ray diffraction patterns (XRD), Fourier Transform Infra-Red (FT-IR), Raman spectroscopy, thermogravimetry (TGA), differential thermal analysis (DTA) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS) analysis. The XRD patterns of the as-prepared and calcined powders exhibit a single phase of hydroxyapatite. The crystallite size of as-prepared and calcined HA is in the range of 44−182 nm. FT-IR and Raman spectroscopy results are in good agreement with XRD ones. The EDS analysis reveals the presence of all elements. The thermal stability of the synthesized powders is evidenced by TGA/DTA scans which show a weight loss smaller than 2%.