Structural and Spectroscopic Studies of Hydroxyapatite Nanorods Formed via Microwave‐Assisted Synthesis Route

In the present investigation Hydroxyapatite [ Ca 10 ( PO 4 ) 6 ( OH ) 2 :( HAp )] nanorods were synthesized using microwave irradiation technique taking ethylene diamine tetra‐acetic acid as a complexing reagent. Hydroxyapatite precursor obtained using microwave irradiation was subjected to differential thermal analysis. Later it was calcined in the temperature range 450°C–900°C. The crystal, grain, and bonding structures of resulting HAp were characterized structurally using X ‐ray diffraction and scanning electron microscopy ( SEM ) techniques and spectroscopically using Fourier transform infrared ( FT ‐ IR ) and R aman techniques. The structural and spectroscopic characterizations of precursor revealed the formation of hydrated HAp . SEM images of the specimens calcined at 600°C and 900°C are presented. This study clearly reveals that nanorods are not formed below 700°C and nanorods are formed only after heat treatment of HAp precursor at 700°C and above. The diameter of nanorods was estimated to be ~200 nm. No nanostructures were found to be formed if the precursor is calcined below 700°C. FT ‐ IR and R aman spectra of HAp samples obtained after calcinations at 700°C and above further confirm the formation of HAp nanorods.