Synthesis and characterization of c-axis oriented apatite aggregates

The aggregates of c-axes oriented hydroxyapatite (HAp) crystallites were synthesized by the hydrolysis of CaHPO4.2H(2)O (DCPD) at 100 degreesC in 10mass% of NaOH solution. The HAp aggregate was of a plate-like form resembling DCPD. The measurements of X-ray diffraction pattern showed that the relative peak intensities of 002 and 004 diffractions increased with synthesis temperature. Some infrared peaks due to CO3 were assigned to B-site substituted carbonate ions in HAp. From FE-SEM observation and XRD measurement, the crystallites in the aggregate were kept in order and their c-axes were perpendicular to the wide surface of an original plate-like DCPD.