The facile and low temperature synthesis of nanophase hydroxyapatite crystals using wet chemistry

• Facile and low temperature nanophase HaP crystals synthesized at pH 11 and 37 °C
• Electron microscopy image of HaP shows characteristic rice grain like morphology.
• FTIR results show the characteristic and fingerprint functional groups of HaP.
• Thermal stability of HaP crystals up to 500 °C
• Growth of Hap crystals occur parallel to c-axis and a possible mechanism proposed

A simple and facile wet chemistry route was used to synthesize nanophase hydroxyapatite (HaP) crystals at low temperature. The synthesis was carried out at a pH of 11.0 and at a temperature of 37 °C. The resulting samples were washed several times and subjected to further analysis. XRD studies revealed that the HaP crystals were polycrystalline in nature with a crystallite size of ~ 15–60 ± 5 nm. SEM-EDXA images confirmed the presence of calcium (Ca), phosphorous (P), and oxygen (O) peaks. Likewise, FTIR confirmed the presence of characteristic phosphate and hydroxyl peaks in samples. Lastly, HRTEM images clearly showed distinctive lattice fringes positioned in the 100 and 002 planes. TGA analysis shows that HaP crystals can withstand higher calcination temperatures and are thermally stable.