Zn_2SiO_4∶Ga蓝紫色长余辉的发光特性

在高温下合成了Zn2SiO4长余辉发光材料;对掺杂Ga后的Zn2SiO4长余辉发光材料的激发光谱、发射光谱、余辉光谱以及衰减曲线进行分析,指出该材料基质中氧缺陷能级和锌缺陷能级是材料的发光中心;掺杂Ga后的GaZn能级能吸收光子,同时能储存电子,停止激发后,储存的电子缓慢释放,从而产生长余辉发光;同时分析了不同Ga掺杂质量分数对发光强度的影响,指出掺杂质量分数为2%时的发光效果最好;并提出了一个材料发光及长余辉发光模型.     

Zn2SiO4:Ga蓝紫色长余辉的发光特性

在高温下合成了Zn2SiO4长余辉发光材料；对掺杂Ga后的Zn2SiO4长余辉发光材料的激发光谱、发射光谱、余辉光谱以及衰减曲线进行分析，指出该材料基质中氧缺陷能级和锌缺陷能级是材料的发光中心；掺杂Ga后的GaZn能级能吸收光子，同时能储存电子，停止激发后，储存的电子缓慢释放，从而产生长余辉发光；同时分析了不同Ga掺杂质量分数对发光强度的影响，指出掺杂质量分数为2％时的发光效果最好；并提出了一个材料发光及长余辉发光模型．     

稀土离子掺杂玻璃的制备与发光性能分析

稀土离子掺杂玻璃是良好的发光基质材料,广泛地应用于激光、光学放大器、光通讯等多方面。该文通过对稀土离子掺杂高硅氧玻璃的制备与发光性能进行分析,旨在提出稀土离子掺杂高硅氧玻璃的制备工艺,充分挖掘稀土离子掺杂高硅氧玻璃的发光性能,为稀土离子掺杂高硅氧玻璃的应用提供理论依据与实践指导。     

掺杂ZnWO4晶体的研究现状与进展

ZnWO4单晶是一种优良的基质晶体材料,过渡金属离子和稀土离子能够较容易地掺杂进去,从而使掺杂ZnWO4晶体具有闪烁发光、上转换发光、可调谐激光等性能。本文从闪烁发光、上转换发光、可调谐激光和大功率LD泵浦发光等几个方面,介绍了掺杂ZnWO4晶体在生长技术、性能测试和发光机理等方面的研究进展。     

Sb掺杂对电纺ZnO纳米纤维的结构与发光性质的影响

Sb掺杂ZnO纳米纤维材料在光电、气敏效应、P型导电等方面具有优异的性质。本文利用静电纺丝方法制备了不同Sb掺杂浓度的ZnO纳米纤维,研究了掺杂对纤维的形貌、结构以及发光性质的影响。发现随着掺杂浓度的提高,纤维的直径增加,晶粒尺寸变大。XRD和Raman的测量表明在掺杂浓度较高的情况下有杂相Zn,Sb2O12的存在。发光测试研究表明,随着掺杂浓度的提高,样品的发光呈现先增强后减弱的变化规律,并且样品发光伴随较强的激光热效应,对于未掺杂样品,由于其直径最小激光的热效应最为显著。     

锆、钛掺杂改性铝酸锶长余辉发光材料性能的研究

应用燃烧法合成了锆、钛掺杂SrAl2O4:Eu2+,Dy3+黄绿色长余辉发光材料,并对材料发光性能进行测试分析.结果表明,锆、钛掺杂能明显改善铝酸锶样品的发光性能.锆、钛的最佳掺杂摩尔比分别为6%和3.75%.     

掺杂浓度对四苯基卟啉掺杂电致发光器件的发光性能影响研究

以8-羟基喹啉铝(Alq3)为主体发光材料,四苯基卟啉(TPP)为掺杂染料,制备了5种不同摩尔掺杂浓度(0．5％、1．0％、1．5％、2．0％、2．5％)的掺杂电致发光器件,考察了掺杂浓度对其器件的电致发光光谱、色度、亮度和发光效率的影响;并结合掺杂器件的发光机理,对实验结果进行了分析和讨论     

电致发光器件中杂质态的引入对器件性能的影响

掺杂对电致发光器件的电学性能和光学性能有着至关重要的影响。本文在总结分析实验结果的基础上 ,提出了一个发光效率随掺杂浓度而变化的理论模型 ,系统地论述了掺杂浓度对器件的电导率及发光效率的影响     

ZnS:TmF3薄膜电致发光特性的研究

为了提高蓝色薄膜电致发光器件(TFEL)的发光亮度,自行配制了氟化铥(TmF3),并制备了以ZnS:TmF3为发光层的薄膜电致发光器件,研究了TmF3的掺杂浓度对ZnS:TmF3 发光器件发光特性的影响.实验结果显示,当掺杂浓度为1.2%mol时,发光亮度最强.     

电致发光器件中杂质态的引入对器件性能的影响

掺杂对电致发光器件的电学性能和光学性能有着至关重要的影响。本在总结分析实验结果的基础上，提出了一个发光效率随掺杂浓度而变化的理论模型，系统地论述了掺杂浓度对器件的电导率及发光效率的影响。     

Management of singlet and triplet excitons for efficient white organic light-emitting devices

Lighting accounts for approximately 22 per cent of the electricity consumed in buildings in the United States, with 40 per cent of that amount consumed by inefficient (approximately 15 lm W(-1)) incandescent lamps. This has generated increased interest in the use of white electroluminescent organic light-emitting devices, owing to their potential for significantly improved efficiency over incandescent sources combined with low-cost, high-throughput manufacturability. The most impressive characteristics of such devices reported to date have been achieved in all-phosphor-doped devices, which have the potential for 100 per cent internal quantum efficiency: the phosphorescent molecules harness the triplet excitons that constitute three-quarters of the bound electron-hole pairs that form during charge injection, and which (unlike the remaining singlet excitons) would otherwise recombine non-radiatively. Here we introduce a different device concept that exploits a blue fluorescent molecule in exchange for a phosphorescent dopant, in combination with green and red phosphor dopants, to yield high power efficiency and stable colour balance, while maintaining the potential for unity internal quantum efficiency. Two distinct modes of energy transfer within this device serve to channel nearly all of the triplet energy to the phosphorescent dopants, retaining the singlet energy exclusively on the blue fluorescent dopant. Additionally, eliminating the exchange energy loss to the blue fluorophore allows for roughly 20 per cent increased power efficiency compared to a fully phosphorescent device. Our device challenges incandescent sources by exhibiting total external quantum and power efficiencies that peak at 18.7 +/- 0.5 per cent and 37.6 +/- 0.6 lm W(-1), respectively, decreasing to 18.4 +/- 0.5 per cent and 23.8 +/- 0.5 lm W(-1) at a high luminance of 500 cd m(-2).     

High-efficiency fluorescent organic light-emitting devices using a phosphorescent sensitizer

To obtain the maximum luminous efficiency from an organic material, it is necessary to harness both the spin-symmetric and anti-symmetric molecular excitations (bound electron-hole pairs, or excitons) that result from electrical pumping. This is possible if the material is phosphorescent, and high efficiencies have been observed in phosphorescent organic light-emitting devices. However, phosphorescence in organic molecules is rare at room temperature. The alternative radiative process of fluorescence is more common, but it is approximately 75% less efficient, due to the requirement of spin-symmetry conservation. Here, we demonstrate that this deficiency can be overcome by using a phosphorescent sensitizer to excite a fluorescent dye. The mechanism for energetic coupling between phosphorescent and fluorescent molecular species is a long-range, non-radiative energy transfer: the internal efficiency of fluorescence can be as high as 100%. As an example, we use this approach to nearly quadruple the efficiency of a fluorescent red organic light-emitting device.     

罗丹明B掺杂ZnQ2的电致发光器件及其性能研究

将8-羟基喹啉锌(ZnQ₂)和8-羟基喹啉铝(AlQ₃)的发光性能进行比较,筛选出ZnQ₂作为掺杂发光层主体材料,与荧光染料罗丹明B(RhB)共掺杂,采用真空热蒸镀法制备有机电致发光器件(OLEDs).掺杂不同浓度RhB可以获得不同波长的光发射,得到不同的发光色调.通过对溶液态荧光光谱和器件发光光谱等特性的测量与分析,探讨了器件的能量转移及发光机理.     

Electroluminescent device with reversible switching between red and green emission

Research on new materials for organic electroluminescence has recently focused strongly on phosphorescent emitters, with the aim of increasing the emission efficiency and stability. Here we report the fabrication of a simple electroluminescent device, based on a semiconducting polymer combined with a phosphorescent complex, that shows fully reversible voltage-dependent switching between green and red light emission. The active material is made of a polyphenylenevinylene (PPV) derivative molecularly doped with a homogeneously dispersed dinuclear ruthenium complex, which fulfils the dual roles of triplet emitter and electron transfer mediator. At forward bias (+4 V), the excited state of the ruthenium compound is populated, and the characteristic red emission of the complex is observed. On reversing the bias (-4 V), the lowest excited singlet state of the polymer host is populated, with subsequent emission of green light. The mechanism for the formation of the excited state of the PPV derivative involves the ruthenium dinuclear complex in a stepwise electron transfer process that finally leads to efficient charge recombination reaction on the polymer.     

Red organic light emitting device with improved performance using a novel fluorescent dye codoped with phosphor-sensitizer

Efficient red organic light-emitting device consisted of a compound fluorescent-phosphor-sensitized emission layer was fabricated. A novel red fluorescent dye, 3-(dicyanomethylene)-5,5-dimethyl-1-(4-dimethylamino-styryl) cyclohexene (DCDDC), and a green phosphorescent dye, fac tris(2-phenylpyridine) iridium [Ir(ppy)3] were codoped into a host material 4,4’-N,N’-dicarbazolebiphenyl (CBP). By adjusting the component ratio of doping system, a series of devices with different concentration proportion of Ir(ppy)3:DCDDC were constructed. The results demonstrated that the device with 0.2 wt% DCDDC had a maximum power efficiency (η_p) of 2.12 lm/W at a current density of 0.1 mA/cm², which was about 38% higher than that of conventional fluorescent device. When at a current density of 4 mA/cm2 (100 cd/m²) and 52 mA/cm² (1000 cd/m²), the η_p percentage was about 160% and 143% higher than that of conventional device, respectively. A stable red light emission at a peak of 615 nm with Commissions Internationale de l’Eclairage coordinates near the region of (0.56, 0.42) in a wide bias range was also obtained. The improved performances were attributed to the efficient multiple-stage energy transfer from the host to the guest and the suppression of loss mechanism.     

Te掺杂ZnSe/[(CdSe)_l(ZnSe)_3]_m超晶格荧光光谱

对垒区Ｔｅ掺杂浓度不同的ＺｎＳｅ／［（ＣｄＳｅ）１（ＺｎＳｅ）３］ｍ短周期超晶格量子阱的稳态和瞬态荧光进行了实验研究，通过不同激发强度下逐级饱和过程测得ＺｎＳｅ垒区自由激子寿命为３５ｐｓ，［（ＣｄＳｅ）１（ＺｎＳｅ）３］７阱区自由激子寿命为１７７ｐｓ，束缚在不同ｎ值的Ｔｅｎ束缚激子的复合寿命为０．５～１０ｎｓ．揭示了Ｔｅ掺杂浓度对能量传递、荧光波长和荧光寿命的灵敏的影响及其规律．     

直接带隙Ge/Si_(1-x)Ge_x量子阱中激子态和带间光跃迁

利用有效质量近似和变分原理,对直接带隙Ge/Si1-x Gex量子阱中激子态和带间光跃迁进行研究.结果表明:直接带隙Ge/Si1-x Gex量子阱中带间光跃迁能、激子复合时间和基态振子强度依赖于阱宽和Si1-x Gex中Ge含量.当阱宽大于30nm时,跃迁能、激子复合时间、振子强度对Ge含量和阱宽的变化不敏感;基态线性光极化率随着Ge含量的增加而减小,同时光极化率峰值所对应的光子能量减小.     

高效蓝色有机发光材料与器件

有机半导体由于具有柔软性而可卷曲成形,具有可溶加工性而采用印刷成膜,从而使得加工成本有可能大大降低而受到广泛关注．本文针对有机发光材料中n型材料不足及宽能带与高电子传输性不可同时实现的难题,我们设计与合成了一系列的宽带电子传输材料并应用于蓝色磷光器件,实现了将近100％的内量子效率蓝色磷光．针对蓝色发光材料色度不纯的问题,我们设计了深蓝色荧光材料,其器件色度坐标CIE（0．15,0．08）,与NTSC标准蓝光相当接近,同时实现接近理论极限的外量子效率发光．针对器件中由于平面波导及表面等离激元等能量模式的损失,我们利用有机材料的自团聚现象在有机发光器件金属阴极上制备无规的纳米结构,把束缚能量转化成自由光子,使得顶出光效率提高到2．1—2．7倍,且不改变原有器件的发光光谱形状．     

C102和Rh6G在SiO2中的荧光光谱

为了提高染料激光器激光介质的波长范围和发光稳定性，在SiO2凝胶基质中掺杂混合染料：香豆素102和若丹明6G掺杂后的荧光光谱可调谐波长展宽．而且两种染料之间能量传递效率提高．     

红色有机薄膜电致发光器件

研制了三种以 8-羟基金属螯合物 Mq3(M=Al,Ga,In)为基质、DCJTB为掺杂剂的红色有机电致发光器件 ,对比了不同掺杂浓度下的 Mq3的光致发光光谱、电致发光的亮度 -电压、亮度 -电流关系 ,从光谱重叠、能级匹配角度分析了不同基质对发光效率及色度的影响