Investigation of microstructure and physical properties of hydroxyapatite based bioceramic materials producted by sol gel method

In present work, Mg, Zn and Al doped hydroxyapatite bioceramics were prepared by Sol-gel method. The structural properties of the samples were investigated using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy techniques. The electrical resistance and dielectrical parameters of the samples were measured by DC and AC measurements.The crystal structures of all the samples were changed with the content of dopant. The degree of crystallization is decreased with increasing content of dopant. X-ray diffraction results show that the samples are from the nanocrystals. All the samples are electrically insulator due to their electrical resistances of 1x1011 ?. The dielectric constants of the samples were changed by the content of dopant. It is found that the alternating current conductivity mechanism of the samples is controlled by hopping mechanism. The density values of Zn- and Al-doped samples are increased with increasing the amount of the dopant, but the density values of the Mg-doped samples are decreased with increasing the amount of Mg. FTIR spectra analysis indicates the presence of the phosphate and hydroxyl groups, especially, in the structure of the samples. The structural and chemical compositions of the samples were changed with depending on type and amount of the dopant.