Study On Preparation And Properties Of Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺ Blue Long Afterglow Materials

Long afterglow luminescent materials are a kind of luminescent materials which userare-earth ions as activators. In the lighting conditions they can absorb and store energy, andthen in the darkness of the conditions they can shine for a long time. With the increasingseriousness of energy problem, long afterglow luminescent materials considered as a kind ofgreen energy materials have attracted more and more attention. In the textile engineering field,long afterglow luminescent materials can mix with PET, PA or PP to spin in order to getluminescent fibers, which can use in luminescent embroidery, clothing adornment and yarndyed fabric. Long afterglow luminescent materials and coating can also be mixed in order toget luminescent coating. Luminescent coating can coat on the fabric, which can be made intoluminescent plush toys.Silicate long afterglow luminescent materials are applied in some fields because of itsadvantages, such as great luminous property, no radiation and pollution, and stable chemicalproperties. In my paper, Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺blue long afterglow luminescent materials wassynthesized through solid-state reaction and sol-gel method. Firstly, choose solid-statereaction to synthesize Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺. Through changing calcination temperature anddopant amounts of Eu²⁺and Dy³⁺, the crystal structure, afterglow property andthermoluminescence spectrum are studied. Then, compared with those of SrAl2O4:Eu²⁺,Dy³⁺,acid and alkali resistance of Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺are studied. The crystal structure, surfacemorphology, excitation and emission spectrum and afterglow property of Sr₂MgSi₂O₇: Eu²⁺,Dy³⁺basically have no change, which highlights the excellence of chemical stability.Secondly, through synthesizing Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺long afterglow luminescentmaterials by sol-gel method, analyzing the effect of crystal structure, excitation and emissionspectra and afterglow property to different reduction atmosphere. It is important to choosingsuitable reduction atmosphere when Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺is synthesized by sol-gel method.No matter how much the precursor body do good, if reduction atmosphere is wrong, theluminous property is still not good performance.Lastly, comparing and analyzing each property of the two synthesizing methods, whichare solid-state reaction and sol-gel method. The afterglow initial intensity of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺synthesized by sol-gel method is less than that of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺synthesized by solid-state reaction. But the afterglow time of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺synthesized by sol-gel method is more than that of Sr₂MgSi₂O₇:Eu²⁺,Dy³⁺synthesized bysolid-state reaction. The afterglow decay curves of the two synthesizing methods intersectat a point. Sr₂MgSi₂O₇:Eu²⁺, Dy³⁺synthesized by sol-gel method has two lattice trap, andSr₂MgSi₂O₇:Eu²⁺,Dy³⁺synthesized by solid-state reaction has one. Sr₂MgSi₂O₇: Eu²⁺,Dy³⁺synthesized by sol-gel method can capture more carriers. The velocity of releasing the carriersis slower than that of Sr₂MgSi₂O₇: Eu²⁺, Dy³⁺synthesized by solid-state reaction, but can lastmore time.