Author(s)

Antonio Zanotto, Maria Luisa Saladino, Delia Chillura Martino, Eugenio Caponetti

Centro Grandi Apparecchiature-UniNetLab, Università degli Studi di Palermo, Palermo, Italy.
Centro Grandi Apparecchiature-UniNetLab, Università degli Studi di Palermo, Palermo, Italy; Dipartimento di Chimica “S. Cannizzaro”, Università degli Studi di Palermo, Palermo, Italy.
Dipartimento di Chimica “S. Cannizzaro”, Università degli Studi di Palermo, Palermo, Italy.

The aim of this work is to investigate the effects of thermal treatment, in the range of temperature between 80^oC - 900^oC, on crystallinity, morphology and particles size of calcium hydroxylapatite nanopowders (HAp). A complete study was carried out applying ³¹P Magic Angle Spinning NMR, X-ray diffraction, nitrogen porosimetry and Transmission Electron Microscopy techniques. HAp specimens were prepared by chemical precipitation in an aqueous solution of calcium nitrate and ammonium hydrogen phosphate. The thermal treatment performed, showed the formation of crystals whose appearance has three main morphologies and different particles size. HAp treated up to 500^oC showed a set of needle-like shape crystals with a low surface area value. These crystals turned into rod-like crystals with temperature increase, along with an increase in crystallite size. At 900^oC was detected a hexagonal hydroxylapatite phase. Furthermore, Dynamic Light Scattering explored a stable HAp dispersion. The isopropyl alcohol dispersion resulted stable for at least two weeks, useful to create layers of determined morphology nanoparticles.

Hydroxylapatite; Precipitation; Thermal Treatment; Alcohol Dispersion

Zanotto, A. , Saladino, M. , Martino, D. and Caponetti, E. (2012) Influence of Temperature on Calcium Hydroxyapatite Nanopowders. Advances in Nanoparticles, 1, 21-28. doi: 10.4236/anp.2012.13004.