Calcium hydroxyapatite (Ca10(PO4)6(OH)2, CHAp), tricalcium phosphate (Ca3(PO4)2, TCP) and calcium oxide (CaO) are the main components of inorganic part of human bones. Such synthetic nanocomposites could be very important implantable materials and using as substitute material for human hard tissues (bones and teeth). In this study, an aqueous sol-gel chemistry route has been developed to prepare nanostructured CHAp thin films on stainless steel substrate. For the preparation of thin films dip-coating and spin-coating techniques were used. The final samples were obtained by calcination of coatings for different time at 1000 °C. For the characterization of surface properties, the X-ray powder diffraction (XRD) analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM) and the contact angle measurements were recorded.

In this study, investigation of the Ca-P-O, Ca:Zn-P-O, Ca:Na-P-O, and Ca:Zn:Na-P-O precursor gels prepared using EDTA as complexing agent and slightly different starting materials was performed. For this purpose, thermal decomposition of the gels was studied by TG/DTA-EGA/MS with following evolvement of H 2 O, CO 2 , NH 3 , and NO x gases. Besides, thermal decomposition products were characterized by Fourier transform infrared spectroscopy, X-ray diffraction analysis, and scanning electron microscopy. It was demonstrated that thermal decomposition of Ca-P-O acetate and Ca:Zn-P-O, Ca:Zn:Na-P-O acetate-nitrate gels is different. Thus, the results of thermal decomposition of Ca:Zn-P-O and Ca:Zn:Na-P-O gels showed that Zn and Na additives accelerate decomposition of the gels. In addition, Na substitution at Ca sites creates conditions for the formation of the orthophosphate composites at lower temperatures.