Synthesis,Properties,and Applications Of The Rare Earth Oxysalt Luminescent Materials With Diverse Morphologies

Rare earth luminescent materials are superior to other materials in terms of their spectroscopic properties due to the rich orbital energy levels and unique 4f electronic transitions,and are widely used in fields such as biomedicine,display imaging,optical materials.The properties of rare earth luminescent materials are greatly affected by the morphology,size,and dimensions of the materials.Therefore,the controllable synthesis of morphology,size and other parameters with inorganic micro/nano materials is of great significance,which is also an important foundation and a key step to achieve material performance regulation.In this paper,a series of rare earth oxysalt materials with good dispersibility,uniform size,and high crystallinity were synthesized by simple chemical method.The phase composition,morphology,and luminescence properties of the materials have been studied in detail.The main content is divided into the following three parts:A series of 3-aminophenol-formaldehyde resin microspheres?APF?with uniform size and good dispersibility were synthesized by the hydrothermal method.Hollow spherical GdPO₄ was prepared by urea homogeneous precipitation and solvothermal method with the APF as template.During the experimental synthesis,the morphology and dispersion of the samples were adjusted by changing the solvothermal temperature and the addition of CTAB.The as-obtained products exhibit good luminescence and paramagnetic properties,good drug loading capacity and sustained release performance,and have great prospects in the fields of dual-mode imaging and drug delivery.A series of YBO₃ microcrystals with different morphologies and good dispersibility have been synthesized by a simple two-step method with H₃BO₃,urea,and Y?NO₃?₃aqueous solution as raw materials.Deionized water and ethylene glycol are used as solvents in the synthesis process without any other surfactants.The reaction temperature and time play a vital role in regulating the morphology and size of the product.The appropriate amounts of Eu³⁺,Tb³⁺,and Yb³⁺/Er³⁺are doped into the YBO₃ samples which show their corresponding characteristic emission.Moreover,YBO₃ samples show excellent multicolor emissions by co-doping different concentrations of Eu³⁺and Tb³⁺,indicating that the YBO₃ materials may be applied as good luminescent host materials.A series of well-defined NaGd?MoO₄?₂ microcrystals with various morphologies and good dispersion have been prepared by a hydrothermal method.NaGd?MoO₄?₂ samples with morphologies such as tetragonal plate,rounded tetragonal plate,tetrahedron,octahedron,etc.were prepared by changing the molar ratio of reactants,hydrothermal temperature and time.The Eu³⁺,Tb³⁺,Dy³⁺,and Sm³⁺doped NaGd?MoO₄?₂ phosphors show excellent down-conversion luminescence performance.The Yb³⁺/Er³⁺,Yb³⁺/Tm³⁺,and Yb³⁺/Ho³⁺doped phosphors exhibit bright up-conversion characteristic emissions.The LED devices manufactured by phosphors and LED chips exhibited good electrical-to-luminous properties,providing the possibility for the application of NaGd?MoO₄?₂ in the fields of LEDs and optoelectronic displays.