Electrospinning Synthesis Of Rare Earth Ions-doped Rare Earth Oxysulfides And Their Luminescent Properties

Rare earth oxysulfides are extensively used as luminescent matrix owing to their high absorption of light and energy transfer efficiency, and have become one of the major optical functional materials.They have been widely applied in the fields of color display, back light,biomedical,etc.Rare earth oxysulfides have become one of the popular research subjects in the realm of optical functional materials in recent years. Nowadays, research on rare earth oxysulfides nanomaterials is focused on nanoparticles. However, one-dimensional or quasi-one-dimensional nanomaterials have many novel properties. In order to study these properties, preparation techniques of rare earth oxysulfides nanofibers and nanobelts are imperatively needed. Electrospinning has attract much attention of researchers and has been proved to be one of the best methods to fabricate low-dimensional nanomaterials owing to its simple operation, high efficiency and reproducibility.etal.For the first time, Ln2O2S:RE3+(Ln=Y,Gd;RE=Eu,Tb,Nd,Yb/Er) nanofibers and nanobelts were fabricated via electrospinning combined with sulfurization technique in this dissertation. Sol-gel process was applied to fabricate the precursor sol of certain viscosity using PVP and various rare earth nitrate salts as starting materials, and electrospinning technique was used to prepare PVP/rare earth nitrates composite nanofibers and nanobelts. Ln2O3:RE3+(Ln=Y,Gd;RE=Eu,Tb,Nd,Yb/Er) were prepared by calcination of the electrospun PVP/[rare earth nitrate] composite nanofibers and nanobelts at700℃for8h,then Ln2O2S:RE3+(Ln=Y,Gd; RE=Eu,Tb,Nd,Yb/Er) nanofibers and nanobelts were synthesized by sulfurization of as-prepared rare earth oxides nanofibers and nanobelts using S powder as sulfur source.The samples were characterized by x-ray diffractometry(XRD), field emission scanning electron microscope(FESEM), transmission electron microscope(TEM), fluorescence spectroscopy and brandband dielectric spectrometer. The results showed that Ln2O3:RE3+(Ln=Y,Gd;RE=Eu,Tb,Nd,Yb/Er) nanofibers and nanobelts were cubic instruction, Ln2O2S:RE3+(Ln=Y,Gd;RE=Eu,Tb,Nd,Yb/Er) nanofibers and nanobelts were hexagonal instruction. The diameter was ca.60-200nm, the width of nanobelts was2-8μm, and the thickness was ca.80-180nm.Some meaningful results were obtained, and laid solid foundations for the future study of luminescence or up-conversion luminescence of rare earth ions-doped rare earth oxysulfides low-dimensional nanomaterials.