我国研制成功等离子显示器用高亮度发光材料

显示设备正经历着真正纯平化的转变,PDP(Plasma displaypanels)作为梦想中的壁挂电视,被认为是本世纪实现平板显示最有力的高新技术之一。它具有大画面、超薄、超轻、广阔的视角(超过160度)、使用寿命长、不受磁场干扰等优点。在PDP中,用等离子气体发出的真空紫外线激发三种无机发光材料,发出红、绿、蓝三种颜色     

助熔剂法制备的(Ce0.67,Tb0.33)MgAl11O19绿色荧光粉的发光性能

选取典型的助熔剂,利用助熔剂法制备了节能灯用(Ce0.67,Tb0.33)MgAl11O19绿色荧光粉,并对其发光性能进行了对比测试。研究了各单一或复合助熔剂对(Ce0.67,Tb0.33)MgAl11O19荧光粉的发光亮度及颗粒形貌的作用及影响,并找到了最佳复合助熔剂组分为0.2%H3BO3+2.0%Li2CO3+2.0%AlF3(质量分数)。所制备的(Ce0.67,Tb0.33)MgAl11O19荧光粉样品具有较为规则的形貌,且发光亮度与(Ce0.67,Tb0.33)MgAl11O19现有商用粉的比值为103:100。     

Hydrothermal Synthesis and Vacuum Ultraviolet-Excited Luminescence Properties of Novel Dy^3＋-doped GdPO4 White Light Phosphors

Novel Dy^3＋-doped GdPO4 white light phosphors with a monoclinic system are successfully synthesized by the hydrothermal method at 240℃. The strong absorption at around 147nm in the excitation spectrum is assigned to the host absorption. It is suggested that the vacuum ultraviolet excited energy is transferred from the host to the Dy^3＋ ions. The f - d transition of the Dy^3＋ ion is observed to be located at 182nm, which is consistent with the calculated value using Dorenbos＇s expression. Under 147nm excitation, Gd0.92PO4：0.08Dy^3＋ phosphor exhibits two emission bands located at 572 nm （yellow） and 478 nm （blue）, which correspond to the hypersensitive transitions ^4 F9/2-^6 H13/2 and ^4 F9/2-^6 H15/2. The two emission bands lead to the white light. Because of the strong absorption at about 147nm, Gd0.92PO4：0.08Dy^3＋ under vacuum ultraviolet excitation is an effective white light phosphor, and has promising applications to mercury-free lamps.     

节能灯用BaMgAl10O17:Eu2+,Mn2+荧光粉的劣化机理研究

对节能灯用BaMgAl₁₀O₁₇: Eu²⁺,Mn²⁺荧光粉的热劣化和紫外辐照劣化机理进行了对比研究. 发现热处理和紫外辐照处理均对BaMgAl₁₀O₁₇: Eu²⁺,Mn²⁺产生明显的发光劣化作用. 研究结果表明：热劣化主要涉及到Eu²⁺ 的氧化及其格位偏移, 而紫外辐照劣化与上述过程无关. 紫外辐照劣化主要源自高能紫外辐照使Eu²⁺ 处于更加不稳定的状态, 从而降低Eu²⁺ 的直接吸收和发射强度.     

BaGa2Si2O8∶Eu^2+,Eu^3+,Pr^3+的发光性质及其防伪加密应用

采用高温固相法在单一基质中制备了具有多模态发光特性的系列荧光粉BaGa2Si2O8∶Eu2+,Eu3+,Pr3+,掺入适量的Pr3+可显著改善荧光粉的余辉发光性能。结果表明,该系列荧光粉在254 nm或365 nm的光激发下,具有不同颜色的光致发光和余辉发光,体现出多模发光特征;同时该系列荧光粉的余辉发光还具有不同的衰减时间。根据这些发光特性,选用合适的荧光粉制作了系列发光图案。相关典型应用示例表明,该发光图案的多模发光特征可应用于发光防伪应用,而基于其差异化的余辉衰减特性,还可以设计出可动态变化的余辉发光图案,从而增加发光防伪和加密的安全层级。     

我国研制成功等离子显示器用亮度发光材料

显示设备正经历着真正纯平化的转变，PDP(Plasma display panels)作为梦想中的壁挂电视，被认为是本世纪实现平板显示最有力的高新技术之一。它具有大画面、超薄、超轻、广阔的视角(超过160度)、使用寿命长、不受磁场干扰等优点。在PDP中，用等离子气体发出的真空紫外线激发三种无机发光材料，发出红、绿、蓝三种颜色     

Photoluminescence and persistent luminescence properties of non-doped and Ti4+-doped Mg2SnO4 phosphors

Mg₂SnO₄ exhibits green photoluminescence and persistent luminescence, which originate from oxygen vacancies. When Ti⁴⁺ ions were doped, an interesting Mg₂SnO₄:Ti⁴⁺ phosphor with bluish white photoluminescence under ultraviolet irradiation and with green persistent luminescence was first obtained. Our investigation reveals that two emission centres exist in Mg₂SnO₄:Ti⁴⁺. The centres responsible for the green emission are considered to be the F centres (oxygen vacancies) and the blue centres are the TiO₆ complex. Trap clusters in the band gap with different depths, such as [Sn_Mg^‥—O_i^″], [Sn_Mg^‥—V_O^·], [Sn_Mg^‥—V_O^×] and Mg_Sn^″, correspond to the components at 85 ℃, 146 ℃ and 213 ℃ of the thermoluminescence curve.     

Ca2GeO4 ∶Eu3+ 的电子结构和紫外-真空紫外发光特性的研究

采用高温固相法合成了发光材料Ca₂GeO₄ ∶Eu³⁺ ,并详细研究了其紫外-真空紫外发光特性. 发现并解释了Eu³⁺ 离子在空气中的自还原以及在不同波长激发下的颜色转换现象. Ca₂GeO₄ ∶Eu³⁺ 在163—230和301,466 nm处具有强激发带,表明Ca₂GeO₄ ∶Eu³⁺ 关键词： 2GeO₄ ∶Eu³⁺')" href="#">Ca₂GeO₄ ∶Eu³⁺ 光致发光机理 空气中自还原 颜色转换     

Photoluminescence degradation mechanism of BaMgAl10O17：Eu2＋ phosphor by vacuum ultraviolet irradiation

<正>A real high power vacuum ultraviolet light source is applied to the investigation on the vacuum ultraviolet irradiation degradation of BaMgA₁₀O₁₇:Eu²⁺ phosphor.The degradations of emission intensity and color quality of the sample are clearly observed after irradiation.It reveals that the oxidation of Eu²⁺ during irradiation is partly responsible for the degradations.The excitation and absorption spectra show that some traps generated during irradiation have negative influence on the luminescence of sample and these traps have been identified as positively charged oxygen vacancies by positron annihilation.The investigations on host emission and decay curve further confirm that these oxygen vacancies are involved in the perturbation of energy transfer from the host to Eu²⁺ and finally result in the degradation.