The hydroxyapatite (HA) bioceramic was synthesized using a sol-gel processing route of calcium nitrate with
trimethyl phosphate and diethyl phosphite. The formation of hydroxyapatite and other compounds during the heattreatment cycle were identified and characterized using
1
H NMR, FTIR, X-ray diffraction spectroscopy. Aging effect on
the phase evolution of water-based sol-gel process to synthesize hydroxyapatite was studied in terms of aging time and
using different phosphorus precursors. The use of diethyl phosphite has improved the sol-gel procedure by eliminating
the aging period that was required for trimethyl phosphate.