Synthesis and characterization of Ce-substituted hydroxyapatite by sol–gel method

Both undoped hydroxyapatite (HAp) and three Ce-substituted HAp samples with variable amounts (from 0.5 to 2 at.%) of Ce were synthesized by sol–gel method. The samples were studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy to determine the crystallite size, crystallinity degree, phases, functional groups, morphology and elemental composition. In all samples, the amount of HAp exceeded 92%, while the amount of admixture β-TCP was always below 8% and no changes were observed by addition of Ce. The crystallinity degree of the samples was always within 84–89%, while the calculated dimensions of crystallites appeared to be within 26–35 nm. The microstructure and elemental composition of all the samples were found to be affected by the addition of Ce.