Investigation of luminescence properties of lanthanide doped natural fluorapatite

It is known that natural apatites are fluorescence. In recent years, considerable studies have been done on 𝐿𝑛3+doped apatites. In this study, the substitutions and luminescence properties of lanthanide ions doped natural fluorapatite structure were investigated. This investigation was carried out in three different ways; effects of sintering temperature, concentration and different cation radii. The substitutions and luminescence properties of lanthanide doped florapatite were investigated by XRD, SEM, FTIR and PL analysis. It was observed that as the sintering temperature of Eu doped florapatite sintered at 1100°C, 1150°C and 1200°C increases, the luminescence property also increases. The samples in which the concentration and the different cation radii were examined were sintered at 1150°C. As the concentration of 𝐸𝑢2𝑂3 doped into the fluorapatite increases, the diffusion of 𝐸𝑢3+ ions and luminescence property were increased. Of 𝐸𝑢3+,𝑆𝑚3+,𝐷𝑦3+,𝐶𝑒3+ 𝑎𝑛𝑑 𝐿𝑢3+ ions with different cation radii, only 𝐸𝑢3+ and 𝑆𝑚3+ ions, whose radii are close to calcium, settle in the fluorapatite structure, whereas 𝐷𝑦3+,𝐶𝑒3+ 𝑎𝑛𝑑 𝐿𝑢3+ ions can not settle in the structure.