No abstract

Single‐phase calcium hydroxyapatite (HAP) was synthesized by a sol–gel route using calcium nitrate solution and ammonium dihydrogen phosphate solution as Ca and P sources and alginic acid as a chelating agent. The dried gel was heat‐treated at different temperatures in the range of 110°–900°C. Structural evolution from sol to gel and from the gel to HAP was studied by the powder X‐ray diffraction method, Infrared spectroscopy, and thermal analyses. The formation temperature of HAP was confirmed to be ∼300°C. Examination of the product obtained at 300°C under TEM suggested the development of hexagonal‐shaped nanoparticles, with the average particle size in the range of 50–100 nm.