Process Parameters on the Crystallization and Morphology of Hydroxyapatite Powders Prepared by a Hydrolysis Method

作者：Wang Moo Chin; Hon Min Hsiung; Chen Hui Ting^*; Yen Feng Lin; Hung I Ming; Ko Horng Huey; Shih Wei Jen

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2013, 44A(7): 3344-3352.

DOI：10.1007/s11661-013-1662-6

The effects of process parameters on the crystallization and morphology of hydroxyapatite (Ca-10(PO4)(6)(OH)(2), HA) powders synthesized from dicalcium phosphate dihydrate (CaHPO4 center dot 2H(2)O, DCPD) using a hydrolysis method have been investigated. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were used to characterize the synthesized powders. When DCPD underwent hydrolysis in 2.5 NaOH solution (Na-(aq)) at 303 K to 348 K (30 A degrees C to 75 A degrees C) for 1 hour, the XRD results revealed that HA was obtained for all the as-dried samples. The SEM morphology of the HA powders for DCPD hydrolysis produced at 348 K (75 A degrees C) shows regular alignment and a short rod shape with a size of 200 nm in length and 50 nm in width. With DCPD hydrolysis in 2.5 M NaOH(aq) holding at 348 K (75 A degrees C) for 1 to 24 hours, XRD results demonstrated that all samples were HA and no other phases could be detected. Moreover, the XRD results also show that all the as-dried powders still maintained the HA structure when DCPD underwent hydrolysis in 0.1 to 5 M NaOH(aq) at 348 K (75 A degrees C) for 1 hour. Otherwise, the full transformation from HA to octa-calcium phosphate (OCP, Ca8H2(PO4)(6)center dot 5H(2)O) occurred when hydrolysis happened in 10 M NaOH(aq). FT-IR spectra analysis revealed that some carbonated HA (Ca-10(PO4)(6)(CO3), CHA) had formed. The SEM morphology results show that the 60 to 65 nm width of the uniformly long rods with regular alignment formed in the HA powder aggregates when DCPD underwent hydrolysis in 2.5 M NaOH(aq) at 348 K (75 A degrees C) for 1 hour.

• 出版日期2013-7