XRD, AFM, IR and TGA study of nanostructured hydroxyapatite

• Main Authors: Mirta Mir, Fabio Lima Leite, Paulo Sérgio de Paula Herrmann Junior, Fabio Luiz Pissetti, Alexandre Malta Rossi, Elizabeth Lima Moreira, Yvonne Primerano Mascarenhas
• Format: Article
• Language: English
• Published: Associação Brasileira de Metalurgia e Materiais (ABM); Associação Brasileira de Cerâmica (ABC); Associação Brasileira de Polímeros (ABPol) 2012-08-01
• Series: Materials Research
• Subjects: nanocrystals; AFM; XRD; hydroxyapatite; Rietveld; TGA e IR
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392012000400021

In this work, the synthetic hydroxyapatite (HAP) was studied using different preparation routes to decrease the crystal size and to study the temperature effect on the HAP nano-sized hydroxyapatite crystallization. X-ray diffraction (XRD) analysis indicated that all samples were composed by crystalline and amorphous phases . The sample with greater quantity of amorphous phase (40% of total mass) was studied. The nano-sized hydroxyapatite powder was heated and studied at 300, 500, 700, 900 and 1150 °C. All samples were characterized by XRD and their XRD patterns refined using the Rietveld method. The crystallites presented an anisotropic form, being larger in the [001] direction. It was observed that the crystallite size increased continuously with the heating temperature and the eccentricity of the ellipsoidal shape changed from 2.75 at 300 °C to 1.94, 1.43, 1.04 and 1.00 respectively at 500, 700, 900 and 1150 °C. In order to better characterize the morphology of the HAP the samples were also examined using atomic force microscopy (AFM), infrared spectrometry (IR) and thermogravimetric analysis (TGA).