掺杂条件对掺寻PVCz薄膜发光性能影响的研究

采用荧光染料Oxazine-720作掺杂剂，对聚乙烯基咔唑（PVCz）进行了掺杂，研究了掺杂溶液浓度，掺杂渐度和掺杂时间对掺杂PVCz膜发光性能的影响，旨在制备高发光效率和发光强度的PVCz膜。     

PtOEP掺杂Alq3有机发光器件的能量传递

研究了高效磷光染料八乙基卟啉铂(PtOEP)掺杂于主体材料八羟基喹啉铝(Alq3)体系中PtOEP、Alq3之间的能量传输机制.分别以PtOEP掺杂和未掺杂的Alq3膜作为发光层制作有机发光器件(OLED),改变掺杂浓度,检测器件电致发光(EL)光谱的变化.经分析,在5%、10%、20%三种掺杂浓度中,10%掺杂浓度能量传递效果最好.通过对掺杂和未掺杂器件电流密度-电压、亮度-电压数据检测,计算外量子效率,在低电流密度(《7mA/cm2)驱动下掺杂器件外量子效率是未掺杂器件的5倍.     

Ge掺杂ZnO薄膜光学特性的研究

采用射频磁控共溅射法在硅基片上沉积了Ge掺杂ZnO薄膜,所制备的样品具有强蓝光发射和弱黄光发射.通过分析Ge掺入量和退火温度对发光谱的影响,并与相同条件下所沉积的纯ZnO薄膜的发光特性进行比较,结果表明,蓝光发射可能与Ge杂质形成的施主能级有关,弱黄峰可能源于Ge替代Zn空位形成的杂质能级到价带的跃迁复合.     

Mg掺杂对ZnO纳米纤维发光性能的影响

采用静电纺丝法在Si基底上制备了不同Mg掺杂浓度的ZnO纳米纤维膜,利用扫描电子显微镜(SEM)、X射线衍射(XRD)、X射线光电子能谱(XPS)、光致发光(PL)等手段对不同Mg掺杂浓度ZnO纳米纤维膜的表面形貌、晶体结构、化学成分、发光性能进行研究。SEM结果表明MgxZn1-xO纳米纤维的直径在50~300nm。XRD结果表明在Mg掺杂浓度低于15%(x=0.15)时,晶体呈现ZnO六角纤锌矿结构,当掺杂浓度达到20%(x=0.2)时,晶体出现MgO的分相。XPS结果表明Mg已成功掺入到ZnO纳米纤维中。PL谱表明MgxZn1-xO纤维膜具有较强的紫外发射,而可见发射几乎观察不到,随着Mg掺杂浓度的增加,紫外发光峰明显蓝移且发光强度增加。     

具有双掺杂发射层白光OLED器件结构的研究

白光有机电致发光器件是获得全色器件的基础。制备了一种具有双掺杂发射层的白光OLED器件，其结构为ITO／CuPc／NPB／ADN：TBP以ALQ：DCJTB／ALQ，Mg：Ag，将2，5，8，11-tetra-tertbutylperylen-e（TBPe）掺杂到蓝光主体材料ADN中作为蓝色发光层，4-（dicyanome-thylene）-2-t-butyl-6-（1，1,7，7tetramethyljul-olidyl-9-enyl）-4H-pyran（DCJTB）掺杂到AIQ中作为红色发光层，通过实验结果对比，研究了TBPe以及DCJTB的掺杂浓度对器件性能的影响，确定了当TBPe浓度为3％（质量分数），DCJTB浓度为1．8％（质量分数），时，获得的白光器件性能最优。     

掺杂ZnO薄膜的研究现状

ZnO薄膜的性质取决于不同的掺杂元素和不同的制备工艺.概述了掺杂ZnO薄膜的研究现状,分析了不同掺杂组分对ZnO薄膜的p型转变特性、发光特性以及铁磁性质的影响,认为稀土掺杂可能使ZnO薄膜产生新的发光特性,共掺杂技术可能是实现ZnO薄膜特性改变的新途径.     

PtOEP掺杂A1q3有机发光器件的能量传递

研究了高效磷光染料八乙基卟啉铂（PtOEP）掺杂于主体材料八羟基喹啉铝（A1q3）体系中PtOEP、A1q3之间的能量传输机制。分别以PtOEP掺杂和未掺杂的A1q3膜作为发光层制作有机发光器件（OLED），改变掺杂浓度，检测器件电致发光（EL）光谱的变化。经分析，在5％、10％、20％三种掺杂浓度中，10％掺杂浓度能量传递效果最好。通过对掺杂和未掺杂器件电流密度-电压、亮度-电压数据检测，计算外量子效率，在低电流密度（≤7mA/cm^2）驱动下掺杂器件外量子效率是未掺杂器件的5倍。     

掺杂材料对蓝光OLED器件性能的影响

采用ADN作为主体材料, 并且对其使用NPB、BAlq3和TBP等材料进行掺杂,制备了一系列蓝光OLED,研究了掺杂对器件性能的影响.实验结果表明,掺杂NPB的器件由于载流子注入和传输趋向平衡,其光电性能明显优于未掺杂的器件; 掺杂BAlq3的器件则具有最佳的色纯度,CIE坐标为(0.15,0.18); 而掺杂TBP的器件则具有高效的能量传递,其流明效率和电流效率分别达到了1.43 lm/W和3.86 cd/A,发光寿命最长,并具有较窄的发光光谱,其色纯度为(0.18,0.19).这些结果说明掺杂不仅改善了器件的发光亮度和色纯度, 而且提高了器件的发光效率和寿命.     

金属掺杂类金刚石膜的研究进展

金属掺杂类金刚石（Diamond—like Carbon,DLC）膜可以优化纯类金刚石膜的很多性能。金属掺杂DLC膜不仅在缓解薄膜应力方面具有良好的效果,而且还能改变薄膜的力学和摩擦磨损性能。目前,掺杂DLC膜正以单一掺杂向复合掺杂、均匀掺杂向梯度掺杂发展。文章对掺杂DLC膜的研究进展作了概括及分析。     

Mn掺杂ZnO纳米线的拉曼散射和光致发光特性

研究了不同Mn掺杂含量的ZnO纳米线在室温条件下的拉曼散射和光致发光性能,发现Mn掺杂入ZnO后引入了部分应力,在其拉曼光谱中表现出拉曼峰的位置发生偏移,Mn的掺杂含量越高,峰偏移得越明显.Mn的掺杂对ZnO纳米线的发光性能也有影响,尽管掺杂后仍保持有较为明显的紫外发光峰,但是,随着Mn含量的增加,紫外发光峰的强度降低,并且半峰宽逐渐增大.此外,Mn的掺杂明显地改变了ZnO紫外发光峰的位置.     

Mg-Al共掺杂ZnO薄膜的制备及其光学特性

采用溶胶-凝胶（sol—gel）旋涂法在载玻片上制备了不同A1掺杂量的Mg—Al共掺杂ZnO薄膜．在室温下利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和光致发光（PL）谱仪等手段分析了Mg—Al共掺杂Zn0薄膜的微结构、形貌和发光特性．XRD结果表明Mg．AI＆掺杂zn0薄膜具有六角纤锌矿结构;随着Al掺杂量的增加,共掺杂薄膜呈C轴取向生长．由SEM照片可知薄膜表面形貌随Al掺杂量的增加由颗粒状结构向纳米棒状结构转变．透射光谱表明共掺杂薄膜在可见光区内的透射率大于50％,紫外吸收边发生蓝移．在室温下的PL谱表明Mg—Al共掺杂zn0薄膜的紫外发射峰向短波长方向移动：Al掺杂摩尔分数为1％和3％的Mg—Al共掺杂ZnO薄膜的可见发射峰分别为596nm的黄光和565nm的绿光．黄光主要与氧间隙有关,而绿光主要与氧空位有关．     

In situ composition and luminescence of terbium coordination polymers/PEMA hybrid thick films

Some terbium coordination polymers with infinite chain polymeric structures were in situ composed with ethyl methacrylate (EMA). With the polymerization of EMA monomer and the formation of terbium coordination polymers of methylbenzoic acid and 2-chloro benzoic acid, the transparent hybrid thick films composed by [Tb(OMBA)₃]_n ([Tb(MMBA)₃]_n, [Tb(OCBA)₃]_n) and poly ethyl methacrylate (PEMA) have been achieved. The luminescence properties and energy transfer for these polymeric composite films were studied with absorption spectra, fluorescent excitation and emission spectra in detail. All the hybrid thick films composed with terbium coordination polymers show the characteristic strong green emission of terbium ions, which implies the same energy transfer mechanism as the pure complex and the hybrid composite film is a suitable substrate for the luminescence of terbium ions. In the range of composing concentration of luminescent species (0.005, 0.01, 0.025, 0.05, 0.1 and 0.2 mmol/7.5 ml EMA), emission intensities increases with the increasing of corresponding composing concentration and concentration quenching effect has not taken place.     

Effect of doping concentration on UV accelerated chemically deposited ZnS:Mn thin films

Pure and Mn alloyed ZnS thin films have been prepared by UV accelerated chemical deposition technique which is simple, economic and easy to monitor. Influence of doping concentration on ZnS thin films was investigated through the structural, compositional, morphological, optical and luminescent studies. The XRD studies confirmed the formation of crystalline films with hexagonal structure. In doped samples the intensities of the prominent peaks increased up to 0.5 wt% Mn and then decreased. The optimum concentration means the amount required to get most suitable characteristics for photovoltaic application. The thickness of the films and the sizes of the crystallites varied in consistent with the structural results. Crystallites became larger in size on doping and appeared to be denser than undoped film. Various structural parameters like stress and micro strain were calculated. The observed strain is compressive in nature which rapidly increased with doping and then remained almost same with doping concentration. The SEM studies revealed the formation of films with almost similar morphology of spherical architectures. All the films exhibited uniform transmission in the high visible region, with a maximum of 80 % for the sample with optimum Mn concentration. Both direct and indirect band gap decreased due to the incorporation of Mn, but showed a blue shift in the fundamental absorption edge with doping concentration up to the optimum dopant content. Undoped and doped films exhibit five distinct luminescence peaks located around 391, 451, 458, 482 and 492 nm. The observed variation in the intensity of the luminescence in doped films clearly indicated the influence of thickness of the films which varied on doping.     

Electrochemical surface plasmon excitation and emission light properties in poly(3-hexylthiophene) thin films

The attenuated total reflection (ATR) and emission light properties utilizing surface plasmon (SP) excitations were measured for the electrochemical change of poly(3-hexylthiophene-2,5diyl) (P3HT) thin films in-situ. The SP emission light could detect the SP excited by molecular luminescence of P3HT. The ATR and SP emission light properties were observed for the doped–dedoped states of P3HT thin film. The ATR and SP emission light properties were remarkably changed with the electrochemical doping and dedoping. The SP emission light also decreased by decrease of the molecular luminescence of P3HT by doping. For the dedoped-state P3HT thin film, SP emission light also increased by increase of the molecular luminescence. The SP emission light excited by molecular luminescence can be controlled by the control of doping–dedoping state.     

Synthesis and luminescence characterization of manganese-activated willemite gel films

Manganese-activated willemite (α-Zn_2 − xMn_xSiO₄; x = 0.05-0.20) phosphor thin films with bright green light emission were deposited on silicon wafers by a sol-gel process. Zinc chloride, tetraethylorthosilicate, and manganese chloride were employed as precursors. The sol-gel transition, crystallization process and photoluminescence of processed films were investigated. The level of manganese doping did not greatly affect the crystallinity, but did affect the gelation rate and luminescence of films. X-ray diffraction and infrared spectrum studies revealed that single-phase willemite started to crystallize at around 600 °C. After thermal annealing at 600°-1200 °C, the crystallinity of films increased with increasing heating temperature and thickness of films. The emission intensity of the film was strongly related to the crystallinity and deposition conditions. Controlling the dopant content, number of coating layers and annealing temperature could significantly enhance the brightness of the green emission. The luminescence properties of α-Zn₂SiO₄:Mn films are characterized by fluorescence spectra and decay lifetime measurements.     

Yb3+、Ho3+掺杂浓度及晶粒尺寸对NaYF4∶Yb3+,Ho3+上转换材料发光的影响

EDTA作为络合剂,在pH值为5的条件下,采用水热法制备了NaYF4∶Yb3+,Ho3+微米棱柱上转换材料,研究了掺杂浓度和晶粒尺寸对上转换发光特性的影响。实验发现材料发光主要以绿光为主,最佳的Yb3+、Ho3+掺杂浓度分别为25%和1%,高于此值均会出现浓度猝灭效应。通过改变溶液中NaF/NH4HF2摩尔比来调控晶粒的尺寸,发现随着晶体颗粒尺寸的增大,材料中Yb3+浓度增加,从而使上转换发光增强。     

Optical and Electrical Properties of Polycrystalline ZnSe:Li

ZnSe:Li ceramics were prepared by hot-pressing powder mixtures of ZnSe and LiOH at 1050°C under a pressure of 30 MPa. The luminescence spectra of the ceramics are dominated by a red emission centered at 630 nm. With increasing Li concentration, the intensity and width of the red band increase, and the band shifts to shorter wavelengths. The nature of the emission centers and the effect of the doping level on their parameters are discussed. The electrical properties of the ZnSe:Li ceramics can be understood in terms of percolation in heterogeneous systems.     

N-B-Al共掺荧光4H-SiC施主受主对发光性能研究

施主受主共掺杂的荧光4H-SiC可以通过复合发出可见光, 影响其发光性能的一个重要因素是施主-受主掺杂的浓度。本研究通过PVT生长方法制备了3英寸N-B-Al共掺的4H-SiC晶体, 采用Raman光谱、SIMS对晶体的结晶类型和掺杂浓度进行了表征; 采用PL发射谱和激发谱、荧光衰减曲线表征和内量子效率对晶体的发光波长、强度、施主-受主对复合发光性能进行了研究。结果发现, 低浓度Al掺杂样品在室温下发出黄绿色荧光。低浓度Al掺杂在晶体中提供较少的受主; 高浓度B、N掺杂形成施主, 从而贡献充足的电子-空穴对。这些电子-空穴的复合提高了施主-受主对复合的内量子效率, 进而增强光致发光强度, 增加平均发光寿命。     

碳纳米管非金属掺杂对结构和性能影响的研究

通过讨论氮、硼、硅、氟等非金属原子掺杂的碳纳米管,对场电子发射特性的影响。介绍了掺杂在场电子发射、能源电池、气体传感器等领域的研究和应用。掺杂可以增加碳纳米管的缺陷,改变其电子结构。掺杂可使碳纳米管转变为n型半导体或是金属性导体,将提高场发射性能。同时,掺杂亦可使碳纳米管向P型半导体转变,这将不利于场发射性能改善。当场发射性能随着掺杂浓度升高而提高时,存在最佳掺杂浓度值,一旦超出,则场发射性能逐渐下降。因此,研究碳纳米管非金属掺杂具有重要的应用价值。     

掺铈硅酸镥(Lu2SiO5:Ce)晶体的生长与闪烁性能

用Czochralsky方法和铱坩埚感应加热技术生长出了尺寸为φ35mm×40mm的掺铈硅酸镥(LSO:Ce)闪烁晶体.透射光谱表明,由于铈离子的掺入,使晶体的吸收边由纯LSO晶体的195nm红移至380nm.LSO:Ce晶体的紫外激发波长按强度递减的顺序依次为380、333、319和216nm,其光发射为带状谱,波长覆盖范围从390nm至560nm.X射线激发的发射谱具有典型的双峰特征,峰值波长为393nm和.426nm.这些特征与Ce³⁺离子基态能级⁴f₁因自旋-轨道耦合而产生的两个分裂能级和Ce⁺离子在LSO晶体中占据两个不同的结晶学格位有关.