Controllable Synthesis Of Bismuth Tungstate Nanocrystal And Its ?-ray Shielding Properties

? ray is developing rapidly in national defense and civil fields,on the one hand,it brought convenience to human life,on the other hand,it can potentially threat to human health.Theoretical research and application development of ?-ray shields will be more and more important.Traditional protective materials have a high surface mobility and?ray shielding rate is generally low,and they are large and clumsy instrument,which cannot meet with the needs of the people.So it is necessary to develop low toxicity and efficient materials.Bismuth and tungsten are "green metal",they possess great advantages such as low cost,easy fabrication.As main functional components of ?-ray shielding,Bi₂WO₆ are considered as compounds consisting of Bismuth and tungsten,it can effectively absorb the ?-ray and replace traditional lead materials.In this paper,we used a facile wet chemical method to synthesize Bi₂WO₆ nano-crystals with shape and microstructure controlled,and investigated the intrinsic relationship between the properties and the microstructure/morphology of Bi₂WO₆ microcrystals.In this study,the relationships between p H values,temparetures,solvents and phase,morphology,photoluminscence and radiation protection effects were investigated by solvothermal method.The crystalline phase,compositions,morphology,surface area and band gap energy of the Bi₂WO₆ were characterized by X-ray diffraction,scanning electron microscopy,transmission electron microscopy and high resolution transmission electron microscopy absorption spectra.It was found that the p H value had a significant influence on the morphology,photoluminescence properties and radiation shielding properties of the samples.The effects of temprature and solvent on morphology more than phase structure.The synthesis processes of T=220? were optimized,enhanced the crystallinity,photoluminescence intensity and?-ray shielding properties.PS/Bi₂WO₆ of irregular nanosphere exhibited ?-ray shielding rate of 69.51% at a mixed 155 Eu and 22 Na point source of 86.5 ke V,which was much higher than that of conventional shielding materials like Pb WO4.The Ce doped Bi₂WO₆ nanoparticles were prepared by solvothermal method using Ce?NO3?3·6H2O as the Ce source.Ce was in substitution for Bi into the Bi₂WO₆ lattic.The experimental result indicated that crystallinity degree with the increasing of doping concentration,only the X-ray diffractive peaks of the?131?plane and?002?plane when the doping content is 20% mol.The topography changed obviousl after droped.Nanoparticle replaced nanosheets.The gamma ray protection test showed that when the Ce content is 5% mol,the shielding efficiency of the gamma ray reaches the maximum,which is about38.66%.And the shielding rate increases with the increase of powder mass.