Tb3+ ion luminescence monitors β-dicalcium silicate mineralization conversion

Tb3+ doped beta-dicalcium silicate (beta-Ca2SiO4: Tb3+) phosphors with different concentrations of Tb3+ were successfully manufactured by the high-temperature solid-state method. The crystal structures, morphological, chemical composition, and optical performances of these before and after mineralization phosphors were investigated via X-ray diffraction, scanning electron microscopy, energy dispersives X-ray spectroscopy, as well as photoluminescence. The crystal structure of beta-Ca2SiO4 can be stabilized by adding Tb3+ ions. Under 375 nm excitation wavelength, Tb3+ occurs on 5D4 -> 7F5 transition, beta-Ca2SiO4: Tb3+ phosphors exhibit intense green emission which is located at 543 nm. During the mineralization experiment, beta-Ca2SiO4: Tb3+ phosphors showed good biological activity and were rapidly transformed into hydroxyapatite (HA), and its luminescence intensity attenuated synchronously. All results suggest that the mineralization process of beta-Ca2SiO4: Tb3+ can be monitored by observing the change in luminescence intensity of Tb3+ ions.