Quantification of phases present in hydrothermally synthesized hydroxyapatite powders from Indian clam seashell by Rietveld refinement method

Abstract

During the synthesis of hydroxyapatite (HA) powder by hydrothermal reaction via Indian clam seashell, different phases are noticed to form along with HA. This is due to the incomplete forward reaction resulting in the retention of the reactants, absorption of moisture, or backward reaction. In the present work, the weight fraction of different phases for synthesized powders has been calculated through the Rietveld refinement method by using X-ray diffraction data. The reactions are carried out at different temperatures (700°C, 800°C, 900°C, 1000°C, and 1100°C) for several time durations (1 h, 2 h, and 3 h) in various independent hydrothermal reactions. The different phases formed in the synthesized powders were examined by the X-ray diffraction (XRD) technique in our previous study. In the present work, through Rietveld refinement, it is revealed that the powders synthesized at 700, 800, and 900°C for 2 h duration contain the highest amount of HA phase among the various time durations. On the other hand, highly pure HA powders can be prepared at 1000°C, and 1100°C applied for 3 h time. The vibration modes of PO43- tetrahedral for all the synthesized powders are studied through Raman spectroscopy. © 2023, Indian Academy of Sciences.