彩色PDP纳米荧光粉的研究

等离子体显示(PDP)具有超薄、高清晰、大画面等优点而被世界公认是实现壁挂式高清晰度电视(HDTV)的首选技术,而荧光粉对PDP性能起着决定性作用.着重介绍了纳米PDP荧光粉的制备方法及影响发光性能的关键因素,并提出了其研究的技术前景.     

彩色PDP用蓝色荧光粉体的纳米化工艺研究

介绍了一种彩色PDP用蓝色荧光粉体的纳米化工艺，通过此方法，可以制备出比传统的PDP蓝色荧光粉体发光效率更高的纳米级蓝色荧光粉体，同时有效的降低了制备过程的烧结温度。制备的蓝色荧光粉体完全适用于PDP显示设备中。另外，纳米化的小颗粒也为进一步的表面包覆以防止衰减奠定了基础。     

Zn2SiO4：Mn光致发光薄膜的溶胶-凝胶法制备及发光性质的研究

以乙酸锌、氯化锰、无水乙醇、正硅酸为主要原料,用溶胶-凝胶浸渍提拉法在石英片上制得Zn2SiO4：Mn薄膜前驱体,经高温煅烧获得到Zn2SiO4：Mn荧光薄膜,荧光分析其发光性能。     

溶胶-凝胶法和微波辐射法制备Mg2SiO4Mn2＋红色荧光粉制备及发光性质的研究

采用溶胶-凝胶法和微波辐射法制备了Mg2SiO4Mn2＋红色发光材料。研究了以Mg2SiO4为基质,在掺杂Mn2＋的情况下,微波合成时间和Mn2＋的掺杂浓度对发光性能的影响。选择最佳微波合成时间和Mn2＋的掺杂浓度,制备了在410nm激发下,发光中心位于690nm的红色发光材料。     

白光LED用全色荧光粉BaMgSiO4:Eu2+,Mn2+的光谱性质

采用高温固相法首次合成了由Eu2+和Mn2+共激活的硅酸镁钡BaMgSiO4全色荧光粉.BaMgSiO4的晶格结构中含有丰富的阳离子格位,有六配位的Ba(Ⅰ)、九配位的Ba(Ⅱ)和Ba(Ⅲ)以及四配位的Mg,为Eu2+和Mn2+提供了不同环境的占据格位.光谱测试显示BaMgSiO4:Eu2+,Mn2+的发射光谱中有3个发射峰,分别是440nm、510nm、620nm,是合成白光较理想的三基色波带;激发光谱呈宽波带,在300～420nm之间均有较强的吸收,能与紫光InGaN芯片匹配,适用于白光LED.     

Si3N4掺杂氮化对Sr3SiO5:Eu2+荧光粉发光性能的影响

采用高温固相法制备Si₃N₄掺杂氮化Sr_2.99SiO_5-6xN_4x:0.01Eu²⁺荧光粉。采用XRD、EDS和SEM测试结果表明: N^3-进入Sr₃SiO₅基质晶格中取代部分O^2-离子, 形成了单一相Sr_2.99SiO_5-6xN_4x:0.01Eu²⁺固溶体。PL&PLE荧光光谱测试结果显示, Sr_2.99SiO_5-6xN_4x:0.01Eu²⁺荧光粉在344nm紫外光的激发下发射出红橙光, 属于Eu²⁺离子典型的 4f⁶5d¹→4f⁷电子跃迁。随着N浓度的增加, Sr_2.99SiO_5-6xN_4x:0.01Eu²⁺荧光粉发射光谱和激发光谱的强度明显增强。热稳定性测试结果表明, Si₃N₄掺杂氮化能够显著提高Sr₃SiO₅:Eu²⁺荧光粉的热稳定性。通过Arrhennius模型拟合结果表明横向穿越过程(crossover)引起的Sr₃SiO₅:Eu²⁺荧光粉氮化前后的温度猝灭。     

PDP用YGB红色荧光粉的制备技术研究现状

介绍YGB((Y,Gd)BO3:Eu3+)红色荧光粉的结构和发光性能,综述近年来YGB荧光粉制备技术方面的新进展,比较不同制备方法的优缺点,探讨了YGB红色荧光粉当前存在的问题,并展望YGB红色荧光粉制备技术的发展趋势。     

沉淀工艺对合成BaAl12O19:Mn2+绿色荧光粉性能的影响

用化学共沉淀法制备出BaAl12O19:Mn2+绿色荧光粉,并研究了沉淀工艺参数对该荧光粉性能的影响.结果表明,通过严格控制pH值等共沉淀条件,可以获得Al3+、Ba2+、Mg2+、Mn2+离子的完全沉淀,并使其中的Al3+以结晶碳酸铝铵形式沉淀,沉淀产物经1200℃×1h煅烧后得到松软超细粉体;调节料液中Mg的掺杂量,制备出单相BaAl12O19:Mn2+荧光粉;料液滴加速度,陈化时间对荧光粉的颗粒大小和形貌有很大影响,通过试验给出了最佳滴加速度及陈化时间范围;该荧光粉的发光性能与商用荧光粉相当,粒度可控制在1～2μm.     

强磁性纳米Fe3O4/SiO2复合粒子的制备及其性能研究

本文采用液相沉积法制备出了满足免疫磁珠用磁核的粒径和磁性要求的纳米Fe3O4/SiO2复合粒子.考察了不同的制备条件对复合粒子的粒径和磁性能的影响,并借助不同的分析测试手段对复合粒子的性能进行表征.结果表明:该复合粒子的最佳制备条件为正硅酸乙酯(TEOS)的浓度为0.6mol·L-1,Fe3O4/TEOS物质的量的比为5:1,反应温度为50℃,搅拌速度为800rpm;在此实验条件下制得的复合粒子的平均粒径在20nm左右,呈球形且分散较均匀,比饱和磁化强度为60.5emu·g-1.     

Disintegration of microcrystalline Zn2SiO4:Mn phosphor powder

Zn₂SiO₄:Mn (willemite) nanoparticles ～30 nm in size have been prepared by disintegrating microcrystalline willemite powder in a planetary ball mill. X-ray diffraction and scanning electron micros-copy characterization showed that ball milling of the Zn₂SiO₄:Mn powder for 60 min or a longer time ensured complete disintegration of the microcrystalline material and that the crystal structure of the resultant nanoparticles was identical to that of the parent powder.     

Synthesis and Properties of Willemite,Zn2SiO4, and M2+:Zn2SiO4 (M = Co and Ni)

Fine particles of willemite, -Zn₂SiO₄, were prepared by both solution combustion and sol-gel methods. Both processes yield single-phase, large-surface area (26- and 78-m²/g), sinteractive willemite powders. Thermal evolution of crystalline phases was studied using X-ray powder diffraction patterns. The combustion method favors low-temperature formation of willemite compared to the sol-gel method. The powders, when uniaxially pressed and sintered at 1300°C, achieved 78–80% theoretical density. The microstructures of the sintered body show the presence of equiaxed 0.5- to 4-m grains. Blue pigments of willemite doped with Co²⁺ and Ni²⁺ were also prepared by the combustion process.     

硅基光致发光膜:(Zn2SiO4/Si):Tb/Mn的制备

利用溶胶-凝胶涂膜技术及高温固相反应技术,在硅片表面生长了掺铽和锰的两种高效硅基光致发光膜.XRD和吸收光谱分析测试结果表明,当固相反应温度高于850℃时,在硅片表面形成了晶态的Zn2SiO4薄膜.荧光光谱实验结果表明这种利用高温固相反应生成的掺铽或掺锰的Zn2SiO4薄膜的发光强度高,余辉为10ms数量级.本方法制备的硅基发光膜热稳定性及化学稳定性好,有希望与硅集成电路工艺兼容.     

The solidification behaviour of melts in the system Zn2SiO4-Mg2SiO4

The melting and solidification behaviour of various compositions across the system Zn₂SiO₄- Mg₂SiO₄ (willemite-forsterite) was studied by means of photoemission electron microscopy, X-ray diffraction and DTA. The results revealed the peritectic type of the phase system instead of the earlier assumed eutectic one. During the formation of willemite solid solutions by rapid solidification of zinc-silicate-rich melts, grain-boundary enrichment of zinc oxide besides magnesium silicate takes place. From melts richer in magnesium silicate, forsterite solid solution forms primarily. The sluggish process of its peritectic decomposition during cooling and the preferred subsolidus formation of zinc silicate give rise to the formation of a ternary non-equilibrium phase assemblage even at slow cooling.     

Synthesis and luminescence study of Eu3+ in Zn2SiO4 nanocrystals

The sol–emulsion–gel method is used for the preparation of Eu³⁺ doped Zn₂SiO₄ nanoparticles. The luminescence spectra at 613 nm (⁵D₀ → ⁷F₂) and lifetime of the excited state of Eu³⁺ ions doped Zn₂SiO₄ nanocrystals are also found to be sensitive to the concentration (0.25–2.5 mol%) of ions. In case of 1000 °C annealed sample (0.25 mol% Eu³⁺) showed the single component decay of 2.02 ms. However, with increasing the concentration the decay is biexponential. We attribute this to an inter-ion exchange interaction wherein the more rapid decay is due to pair or cluster formation and the longer-lived emission originates from isolated ions within the insulating host.     

White organic light-emitting devices utilizing a mixed color-conversion phosphor layer consisting of CaAl12O19:Mn and Zn2SiO4:Mn

White organic light-emitting devices (WOLEDs) were fabricated utilizing a mixed color-conversion layer consisting of CaAl12O19:Mn and Zn2SiO4:Mn phosphors. The ratio between the CaAl12O19:Mn and the Zn2SiO4:Mn phosphor determined the rate of the red and the green lights. The color rendering index was improved by using a mixed color-conversion phosphor layer.     

SiO2/TiO2催化剂的制备及其光催化性能

利用钛酸四丁酯、正硅酸乙酯、乙酸和水为原料, 通过溶剂热方法制备得到SiO₂/TiO₂催化剂. 产物经XRD、Raman、TEM、BET、FT-IR和XPS表征, 结果表明: 所制备的SiO₂/TiO₂催化剂为比表面积大、结晶度高的锐钛矿TiO₂, SiO₂与TiO₂之间通过Si-O-Ti键结合. 另外, 以亚甲基蓝降解为探针反应, 考察了SiO₂/TiO₂催化剂在紫外光照射下的光催化性能. 结果表明: SiO₂/TiO₂催化剂具有比纯TiO₂更优越的光催化性能, 65min可以将亚甲基蓝(MB)彻底降解.     

Sol-Gel法和微波法合成亚纳米级 Zn2SiO4:Mn2+高效绿色荧光体

采用Sol-Gel法和微波法合成了亚纳米级Zn2SiO4:Mn2+高效绿色光致发光荧光体,考察了Mn2+单掺的荧光体的发光行为及掺杂浓度对产物发光性质的影响. 微波条件下合成的荧光体,有两个激发峰和一个发射峰分别恒定于214、249和522nm , 即它们均不随掺杂离子浓度不同而改变. SEM表明Zn2SiO4:Mn2+粒度为150350nm的不规则的球形.