Controllable Preparation And Characterization Of Y₂O₃ Nanopowders

Yttrium oxide(Y₂O₃),as a rare earth oxide,has a unique 4F electron configuration.Recently,nanoscience has been noticed by more and more researchers.As a rare earth element,yttrium oxide nanopowders have unique properties in terms of magnetism,electricity,light,which makes yttrium oxide nanopowders have unique properties in magnetic,electrical,optical and other aspects.Therefore,Y₂O₃ nanopowders has a broad application prospect in metallurgical machinery,petrochemical industry,electricity,optics,high density structural ceramic sintering,fuel cell,magnetism,catalysis,atomic energy industry and other aspects.In this paper,Y₂O₃ precursor was firstly prepared by precipitation method and solvothermal method,and then Y₂O₃nanopowders were successfully prepared by calcination.The main research results are as follows:(1)The spherical Y₂O₃ nanopowders were prepared by precipitation and calcination of oxalic acid.The effects of the concentration of yttrium nitrate and oxalic acid and dispersant on the morphology and size of the product were studied.The influence of surfactant diffusion mechanism on the morphology and size of precursor,the inhibition mechanism of the agglomeration of precursor after nucleation and the inhibition of the growth of precursor on grain growth during calcination were studied.The Y₂O₃ nanopowders with primary particle size of 50-200 nm can be prepared by adding 0.2 mol/L yttrium nitrate solution to 0.6 mol/L oxalic acid solution added 5 g/L PEG-4000 in reverse and equal volume.The product is calcined at 700?for 3 h.(2)Rod-like Y₂O₃ nanopowders were prepared by solvothermal method and calcination using yttrium chloride as yttrium source.The effects of the concentration of Yttrium Ion in the precursor solution,the p H value of the solution,the volume fraction of ethanol in the solvent and the solvothermal temperature on the composition,morphology and size of the products were systematically studied.The results showed that the concentration of Yttrium Ion in the precursor solution was 0.1 mol/L,the p H was adjusted to 9 with ammonia,the volume fraction of ethanol in the solvent was60%-80%,and the reaction was hydrothermal at 240?for 12 h.The obtained hydrothermal product calcined at 800?for 3 h can produce rod-like Y₂O₃nanopowders with diameter of 30-50 nm and length of about 2?m.(3)Monodisperse spherical Y₂O₃ nanopowders were prepared by urea hydrolysis and calcination using yttrium chloride as yttrium source.The effects of Yttrium Ion,urea concentration and hydrolysis temperature on the composition,particle size and morphology of precursor and final product were studied.0.3 mol/L in precursor solution,0.5 mol/L in urea,85?in hydrolysis temperature and 2 h in hydrolysis reaction time.Spherical Y₂O₃ nanopowders with diameter of about 50 nm was prepared by calcining at 800?for 2 h.(4)Eu doped yttrium oxide Y₂O₃:Eu(Eu:5%)nanopowders were prepared by the above three methods,and their photoluminescence properties were studied.Y₂O₃:Eu nanopowders were excited by 248 nm UV light,and the emission spectrum at613 nm was very obvious,showing a bright red emission.