Studies On Preperation Of Nano-oxysulfide Via Pyrolysis Of Rare Earth Complexes With Sulphur-contaning Ligands

Rare earth oxysulfide have been paid much attention for their promising application in various fields based on the magnetic,optical,and chemical characteristics arising from their f electrons.Diethyldithiocarbamate(Et₂NCS₂^-) complexes compounds of metal with sulfur-containing organic ligands are favor by people for potential applications in synthesis of new materials,because these complexes have unique structure resulting from their the bond of RE-S.In this dissertation,a facile and direct route to prepare rare earth oxysulfide was explored based on the synthesis of ternary complexes compounds,RE(Phen)(Et₂CNS₂)₃(Phen=1,10-phenanthroline),with sulphur-containing ligands.The main research content in this dissertation were summarize as follows:1.Three ternary solid complexes,RE(Phen)(Et₂CNS₂)₃,have been prepared from the reaction of hydrous rare earth chloride/nitrate,sodium diethyldithiocarbamate(Na Et₂CNS₂) and 1,10-phenanthroline in aqueous solution and acetonitrile solution,respectively.The complexes were identified as the general formula of RE(Phen)(Et₂CNS₂)₃ by means of elemental analysis,X-ray Photoelectron Spectroscopy,and structure of the complexes were identified by IR spectroscopy,X-ray powder diffraction.The experimental results revealed that sulfur atoms in diethyldithiocarbamate coordinated to rare earth ions in bidentate fashion and an introduction of an ancillary ligand phen to the complexes played an important role in the stabilities and oxidation resistance of the complexes.The thermolysis behaviors of the complexes have been researched by TG-DTA.The result shows that the complexes were decomposed into RE₂S₃ in one step,indicating that the complexes are excellent single-source precursors to rare earth chalcogenides/oxysulfide.2.In the open air,rare earth oxysulfide nanrods were prepared by the reaction between RE and S source form pyrolysis of the complexes,RE(Phen)(Et₂CNS₂)₃,in organic solvent,and oxygen in the air.Oxysulfides were prepared by decomposition of the complexes in the air,but the flow of oxygen is of key importance.The result shows that reaction temperature and organic solvent are crucial to prepare to rare earth oxysulfide nanocrystals.The shape and size tenability of oxysulfides nanocrystals can be achieved by surfactants,The fluorescent properties of Gd₂O₂S:Eu and Gd₂O₂S:Yb,Er were studied.