Sounchemical synthesis of Graphene/nano hydroxyapatite composites for potential biomedical application

Graphene nanocrystalline hydroxyapatite composites (G/nHA) were prepared using a wet precipitation method with CaCl2 and Na2 HPO4 as the main material in the presence of ultrasonic irradiation. The calcium to phosphate ratio (Ca/P) was adjusted to be about 1.67 while the pH value kept at 9.5-10.5. The texture properties of the G/nHA composites were determined through series of characterization techniques. High-resolution Scanning Electron Microscopy (HR-SEM) and high-resolution Transmission electron microscope (HR-TEM) were employed to determine the particle size and structure morphology of composites. The Crystalline and molecular structure were checked using (XRD), Raman and (FTIR), while thermal decomposition behavior was reported by thermogravimetric analysis (TGA-DTA). Energy dispersive spectroscopy (EDAX) results revealed that the prepared nHA and G2nHA samples had a Ca/P ratio of 1.66 and 1.73 respectively which are nearly matching to previously reported value. FT-IR analysis identified functional groups and confirmed the results obtained from the X-ray diffraction data that the prepared powders were indeed composed of nanoscale hydroxyapatite. The results indicate that nHA successfully prepared through this method and the range of particles was found around nanoscale. The compression test indicates that even the addition of very small amount of Graphene sheets like structure into the crystalline matrix of nHA enhancing the mechanical properties of the prepared composites compared to the pure nHA.