Luminescence and thermoluminescence of Er3+-doped CaF2 nanomaterials

Er3+-doped calcium fluoride (CaF2:Er3+) nanoparticles (NPs) have been synthesized by a chemical co-precipitation method. A solution of water ethanol in a 1:1 ratio was used as a solvent. X-ray diffraction and scanning electron microscopy (SEM) results indicated that the fabricated material had a cubic crystal structure and a characteristic cubic shape of Caionscrystals. The main grain size calculated from Scherer's formula was about 30 nm. The photoluminescence (PL) spectrum of the material showed the specific emissions of Er3+ ion in the CaF2 host lattice and the highest emission intensity was obtained at 2 mol% Er3+ ion. Under a 980 nm laser excitation, the up-conversion luminescence spectra with predominance of red emission were recorded. The thermoluminescence (TL) characteristics of the material were also studied. The obtained CaF2:Er3+ nanocrystals exhibit a high TL sensitivity and linearity to beta (β) radiation doses. The main TL peak is located at 235°C (508 K) and the kinetic parameters corresponding to the trap have been determined by TLAnal software These properties make the phosphor useful for application to estimate exposures of beta rays.