Sol-gel synthesis, phase composition, morphological and structural characterization of Ca-10(PO4)(6)(OH)(2): XRD, FTIR, SEM, 3D SEM and solid-state NMR studies

Abstract

Aqueous sol-gel chemistry route based on ammonium hydrogen phosphate as the phosphorus precursor, calcium acetate monohydrate as source of calcium ions, and 1,2-ethylendiaminetetraacetic acid (EDTA), or 1,2-diaminocyclohexanetetracetic acid (DCTA), or tartaric acid (TA), or ethylene glycol (EG), or glycerol (GL) as complexing agents have been used to prepare calcium hydroxyapatite (Ca-10(PO4)(6)(OH)(2), CHAp). The phase transformations, composition, and structural changes in the polycrystalline samples were studied by infrared spectroscopy (FTIR), X-ray powder diffraction analysis (XRD), and scanning electron microscopy (SEM). The local short-range (nano- and mezo-) scale effects in CHAp were studied using solid-state NMR spectroscopy. The spatial 3D data from the SEM images of CHAp samples obtained by TA, EG and GL sol-gel routes were recovered for the first time to our knowledge. (C) 2016 Elsevier B.V. All rights reserved.