STUDY OF THE LUMINESCENT CHARACTERISTICS OF PURE AND FLUORINE-CONTAINING BIO-HYDROXYAPATITE

This work presents a comparative study of pure and fluorine-containing hydroxyapatite (HAp and HAp–F), focusing on the effect of fluoride ions on the structural and optical properties of the material. The samples were synthesized using a rapid pyrolysis method and characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and luminescence spectroscopy. XRD analysis showed that both materials crystallize in a hexagonal apatite structure with the space group P6₃/m. The FTIR and XRD data suggest structural changes associated with the partial incorporation of F⁻ ions and modifications in the local environment of phosphate groups. The spectral and luminescence measurements revealed that the presence of fluorine affects the luminescence behavior, including changes in the visible spectral region and possible modification of energy-transfer processes. Overall, these findings show that the incorporation of fluorine influences the structural and optical properties of hydroxyapatite and may provide a basis for further studies of apatitebased materials for biomedical and luminescent applications.

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