Effects of composite TiO ₂ on the crystal of hydroxyapatite prepared by sol-gel method

Using sol-gel method, Hydroxyapatite/TiO ₂ composite material was prepared by mixing the Hydroxyapatite (HA) and TiO ₂ sol made from precursor together, and then drying and heat treating the mixed sol. The effect of TiO ₂ on the crystallization of HA was investigated by XRD. By analyzing the XRD data, the effects of TiO ₂ on grain size and crystallinity of HA were studied. The results show that the composite TiO ₂ delayed the crystallization, promoted the grain growth and accelerated the decomposition of HA. The grain size of composite HA is less than 100 nm, and the crystallinity reached up to 90% at the temperature for about 1000°C.