Microstructure analysis and thermal stability of Mg\u3csup\u3e2+\u3c/sup\u3e/Sr\u3csup\u3e2+\u3c/sup\u3e/SO4\u3csup\u3e2-\u3c/sup\u3e ions doped hydroxyapatite bionanomaterials

This study evaluates the influence of the addition of Mg2+, Sr2+, and SO42- ions on the microstructure and thermal stability of hydroxyapatite (HA). The materials were calcined at 500 °C and 800 °C for 2 h, then characterized by XRD, FTIR, SEM, EDX, and FTIR techniques. The degree of crystallinity and crystallite size of HA crystals were significantly decreased with the incorporation of Mg2+/Sr2+/SO42- ions. While the lattice parameters were reduced due to the substitution of ions, The high incorporation of Mg2+ ions lowered the thermal stability of HA. At the same time, the addition of Sr2+ ions enhanced thermal stability. A similar impact on phosphate bands was seen in FTIR results. HA existed in spherical nanoparticles; incorporating Mg, Sr, and S ions doesn’t change the particle shape