白光LED用稀土掺杂磷酸盐荧光粉的制备与发光性能研究

发布时间：2018-09-17 06:52

【摘要】：LED(light-emitting-diode,即发光二极管)作为第四代固态照明光源与传统的照明光源比具有体积小、发热量低、亮度高、使用寿命长、环保、色彩多样等优点。其中紫外光激发的LED与蓝光LED以及三色基LED相比,其颜色可控,均匀度更好。发光材料的性能对紫外LED起着关键的作用,因此寻找适合紫外光LED用荧光粉非常重要。以磷酸盐体系为基质的荧光粉具有较好的吸收能力和较高的转换效率。基于此,本文进行了以下工作:1.采用水热法合成了La PO_4:RE(RE=Eu~(3+),Tb~(3+))及Bi PO_4:RE(RE=Dy~(3+),Tb~(3+))两种荧光粉,研究了材料的光谱特性。结果显示La PO_4:Eu~(3+)在394 nm紫外光激发下发射红光,La PO_4:Tb~(3+)在369 nm紫外光的激发下发射绿光。BiPO_4:Dy~(3+)在350 nm紫外光的激发下最终发射白光,BiPO_4:Tb~(3+)在369 nm紫外光激发下产生绿色发光。2.采用水热法合成了Na_3Y(PO_4)_2:RE(RE=Eu~(3+),Tb~(3+))稀土磷酸盐荧光粉,并对其形貌以及光谱性质进行研究。结果表明:该粒子呈现纺锤形,尺寸均一,Na_3Y(PO_4)_2:Eu~(3+)在394 nm紫外光激发下发射红光,Na_3Y(PO_4)_2:Tb~(3+)在369 nm紫外光的激发下呈现绿色发光。3.采用水热法合成了Zn_3(PO_4)_2基质以及Zn_(2.75)(PO_4)_2:Tb_(0.25)~(3+)荧光粉,研究了pH值对该物质形成的影响以及稀土离子掺杂后的光谱特性。结果表明:酸性条件下有利于形成Zn_3(PO_4)_2,中性条件下形成Zn_3(PO_4)_2以及NH_4Zn PO_4的混合物,碱性条件下形成纯相NH_4Zn PO_4,Zn_(2.75)(PO_4)_2:Tb_(0.25)~(3+)最终呈现绿色发光。4.通过高温固相法合成了LiBaPO_4:Dy~(3+)磷光体,并对其光谱性质以及热释光性质进行了研究。结果表明:该物质可以被370~410 nm光激发,最终发射白光,同时是一种良好的热释光材料。
[Abstract]:LED (light-emitting-diode) as the fourth generation of solid-state lighting source has the advantages of small size, low calorific value, high brightness, long service life, environmental protection and color diversity compared with traditional lighting source. The phosphors based on phosphate system have good absorption ability and high conversion efficiency. Based on this, the following work has been done: 1. La PO_4:RE (RE = Eu~ (3+), Tb~ (3+) and Bi PO_4:RE (RE = Dy) were synthesized by hydrothermal method. The results show that La PO_4:Eu~ (3+) emits red light under the excitation of 394 nm ultraviolet light and La PO_4:Tb~ (3+) emits green light under the excitation of 369 nm ultraviolet light. BiPO_4:Dy~ (3+) emits white light under the excitation of 350 nm ultraviolet light and BiPO_4:Tb~ (3+) emits green light under the excitation of 369 nm ultraviolet light. Color luminescence. 2. Na_3Y(PO_4)_2:RE(RE=Eu~ (3+), Tb~ (3+) rare earth phosphate phosphors were synthesized by hydrothermal method, and their morphology and spectral properties were studied. The results showed that the phosphors were spindle-shaped, uniform in size, red in Na_3Y(PO_4)_2:Eu~ (3+) excited by 394 nm ultraviolet light, and Na_3Y(PO_4)_2:Tb~ (3+) in 369 nm ultraviolet light. The Zn_3(PO_4)_2 matrix and Zn_(2.75)(PO_4)_2:Tb_(0.25)~(3+) phosphors were synthesized by hydrothermal method. The influence of pH value on the formation of Zn_3(PO_4)_2 and the spectral characteristics of rare earth ions doped Zn_3(PO_4)_2 were studied. The pure phase NH_4Zn PO_4, Zn_ (2.75) (PO_4) _2: Tb_ (0.25) ~ (3+) was formed by the mixture of NH_4Zn PO_4 under alkaline condition. The green luminescence was finally observed. 4. LiBaPO_4: Dy_ (3+) phosphor was synthesized by high temperature solid-state method, and its spectroscopic properties and thermoluminescence properties were studied. White light is also a good thermoluminescent material.
【学位授予单位】：沈阳师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ422

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