Microstructural Investigation of Fluoroapatite Hydrothermally Converted from Hydroxyapatite Synthesized from Crocodile Eggshell

Fluoro/hydroxyapatite (FHAp) were prepared by hydrothermal at 150 °C for 24 hours with different of starting materials. The conversion of hydroxyapatite (HAp) and tricalcium phosphate to FHAp showed the rod-like shape with 200 nm. While, the morphology of FHAp from crocodile eggshell as CaCO3 form with different in phosphorus and fluoride source showed the unique structure evolution from rod-like hexagonal crystals, dumbbell to ball shape. Two distinctive morphology, first when using NaF as fluoride source with (NH4)2HPO4 precursor show the large cubic structure in high magnification it is tufted hexagonal crystal and it bundle like structure. As the pH value decreases in NH4F, it increases crystal size. For H3PO4 as phosphate precursor found that unique structure evolution from rod-like hexagonal crystals to dumbbell structure and then form the sphere assembly with a size of several micrometers.