Preparation And Luminescence Of Oxide-based Upconverting Nanophosphors

The upconversion nano-labels are the hotspot which are used to research nano-labels for bio-analysis in recent years. How to choose a suitable host material and rare earth ions is the important research direction of the upconversion nano-labels in order to obtain the upconversion materials that have excellent property, high luminous efficiency and morphology. This paper find suitable host materials to obtain the upconversion materials which have appropriate particle size and high luminous efficiency. Different experimental methods were used to prepare a series of rare-earth doped oxides and composite oxide materials and explore their morphology and luminous properties.First, we used low-temperature combustion to prepare Y2O3:Yb,Ho nanoparticles and searched the synthesis conditions and the dispersion of nanoparticles. Through the experiment, we can get Y2O3 at 180℃as ignition temperature, and the optimum amount of glycine is a G/N (glycine and nitrate mole ratio) ratio was 3.5/9, the best reaction time was 60 min, the reaction temperature is 220℃, and PEG 4000 has the certain effect for improving the dispersion of nanoparticles.Next, we used co-precipitation method to prepare SrY2O4:Yb,Er as new composite oxide host material, and studied different experimental conditions such as oxalic acid concentration and pH value that impacted on the upconversion luminescence and morphology of the SrY2O4:Yb,Er sample, and then studied the upconversion mechanism.Third, we used solvothermal method to prepare In2O3:Yb/In2O3:Yb,Er power. We studied the effect of Tm3+/Yb3+ doped concentration, calcination temperature and heating temperature on upconversion and morphology of the In2O3:Yb,Tm sample in detail. And we found the special broadband upconversion emission phenomenon of In2O3:Yb nanoparticle, then study and analyze the causes of this phenomenon.Last, we obtained CaTiO3/CaTiO3:Pr micro-crystal at 200℃without calcining through Ethylene Glycol assisted hydrothermal method. We found the morphology of CaTiO3 would change by the different ratios of ethylene glycol and wate, for example, cube, dodecahedron, microstructure and other spheres. And we analyzed the possible reasons of the formation of various morphology; The preparation process was simple and didn't need high temprature, and we could get products that had high-purity and good dispersion.