Jinghong Song

Synthesis and Characterization of CaF2 Nanoparticles with Different Doping Concentrations of Er3

The calcium fluoride nanoparticles with a variety of doping amounts of erbium ions were prepared by CTAB/C4H9OH/C7H16/H2O reverse micro-emulsion method. The nanoparticles were studied by X-ray diffraction (XRD), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR), absorption and fluorescence spectra. The XRD patterns indicated a typical cubic fluorite structure and no other impurities. The TEM results showed one kind of particles with uniform grain size and without agglomeration were synthesized. The FTIR spectra revealed that there were some amounts of -OH, NO3− and organic groups absorbed on the surfaces of the particles before being annealed. The absorption spectra presented many absorption peaks and bands corresponding to the rich energy levels of erbium ion. The Red-Shift of absorption bands and Blue-Shift of fluorescence peak could attribute to the weakened energy level split as a result of the decrease in crystal field strength.

Preparation of nanometer Nd3+, Y3+ co-doped CaF2 powder by coprecipitation-azeotropic distillation technique

The synthesis of Nd3+, Y3+:CaF2 nanopowder was conducted by azeotropic distillation method, which effectively dehydrated hydrous CaF2 and prevented forming hard agglomerates. X-ray diffraction (XRD), scanning electron microscopy (SEM), scanning calorimetries-thermalgravimetry (DSC-TG), Fourier transform infrared spectroscopy (FT-IR) and absorption spectroscopy were performed to characterize the powder properties. The experimental results showed that products obtained by azeotropic distillation were single phased, rather monodispersed, successfully prevented the hard agglomerate formation and effectively removed the residual water inside the as-prepared precipitate than that of the direct drying. The absorption spectra showed a wider and stronger absorption bands around 792 nm, which should be profitable for LD pumping.