双发光层白光有机电致发光器件的研究

将DCJTB掺杂入Alq3中,作为黄光发光层,制作了一种基于新型蓝光材料PAA的白光有机电致发光器件(OLED).器件的结构为ITO/NPB/PAA/Alq3:DCJTB/Alq3/Mg:Ag,通过PAA层的蓝光与Alq3:DCJTB层的黄光混合实现了很好的白光发射.结果表明,器件在4.6V时启亮,在5.2V时达到最大...     

NPB蓝色有机电致发光器件的性能优化研究

基于结构为ITO/NPB/BCP/Alq3/Mg:Ag的NPB(N,N’-bis(1-naphthyl)-N,N’-diphenyl-1,1’-biphenyl-4,4’-diamine)蓝色有机电致发光器件,利用Alq3的空穴阻挡能力及高的荧光效率优化了器件结构。具有不同厚度Alq3空穴阻挡层的器件性能测试结果表明,Alq3对器件发光亮度影响明显,选择适当的Alq3厚度可使得器件的发光亮度提高大约两倍。电致发光光谱测试结果表明,器件的发光基本来自NPB的蓝色发光,而Alq3扮演了辅助发光层的作用。     

基于NPB的未掺杂高效蓝色有机电致发光器件

采用真空镀膜的方法制备了基于NPB的高效蓝色有机电致发光器件(OLED),其结构为:ITO/NPB/BCP /Alq3/Mg∶Ag和ITO/TPD/NPB/BCP / Alq3/Mg∶Ag,由于BCP对空穴的阻挡作用,器件的发光谱峰均位于441nm处,为NPB的EL特征光谱,实现了蓝色发光.在15V时,器件的最高亮度为2880和3000cd/m2,分别在2.5V和1.5V器件启亮之后,最大流明效率为4.00和5.63lm/W,CIE色坐标为(0.14, 0.08)和(0.15,0.11).     

有机微腔蓝光发射二极管的研制

利用玻璃/DBR/ITO/NPB/NPB:二萘嵌苯/TAZ/Alq/Al器件结构,研制了有机微腔蓝光发射二极管.将激光染料二萘嵌苯掺于空穴传输材料NPB中作为发光层,Alq为电子传输层,为防止未参与复合的空穴到达金属电极,在NPB:二萘嵌苯和Alq之间引入一薄层TAZ,所研制的微腔器件的峰值位于456 nm,器件表现为较纯的蓝光发射,色坐标为x=0.165,y＝0.088.微腔器件的最大亮度为2 500 cd/m2,最大发光效率为0.23 cd/A.     

掺杂Rubrene双发光区有机黄光器件的制作

制作了在N,N′-diphenyl-N,N′-bis-1-naphthyl)-(1,1′-biphenyl)-4,4′-diamine(NPB)和aluminium-tris-8-hydroxy-quinoline(Alq3)中分别掺杂黄色荧光染料5,6,11,12,-tetraphe-nylnaphthacene(Rubrene)的双发光区有机黄光电致发光器件。器件的结构为ITO/NPB(30nm)/NPB∶Rubrene(20nm)/Alq3∶Rubrene(20nm)/Alq3(30nm)/LiF(0.8nm)/Al。NPB作为空穴传输层材料,Alq3作为电子传输材料,NPB和Alq3中掺杂Rubrene的浓度分别为0.9%和1.4%。实验结果表明,由于Rubrene具有较强的载流子俘获能力,而且在Alq3和NPB层中进行掺杂,相对于单掺杂层器件为Rubrene提供了更多的俘获空位,从而提高了器件的性能。     

双异质型蓝色OLED器件的研究

采用真空蒸镀法制备了ITO／NPB／BAlq3／Alq3／Mg：Ag(双异质型)和ITO／NPB／BAIq3／Mg：Ag(传统型)两种结构的蓝色有机电致发光器件(OLED)，并研究了器件结构对OLED光电性能的具体影响。实验结果表明，器件结构对OLED的发光光谱没有影响。其谱峰均位于480nm。但是器件结构却显著影响OLED的发光性能，与传统型结构器件相比，双异质型结构OLED的最大发光效率和最大发光亮度分别提高了4．5倍和5．5倍，达到1．901m／W和10000cd／m^2。这是因为双异质型器件结构中引入了电子传输层Alq3和空穴阻挡层BAlq3，从而使得能级匹配更加合理。载流子注入更加平衡的缘故。     

空穴传输层厚度对有机发光二极管性能的影响

采用聚乙烯基咔唑(PVK)作为空穴传输层,8-羟基喹啉铝(Alq3)作为发光层,制备了结构为ITO/PVK/Alq3/Mg∶Ag/Al的有机发光二极管(OLED),通过测试器件的电流-电压-发光亮度特性,研究了空穴传输层厚度对OLED器件性能的影响,优化了器件功能层的厚度匹配.实验结果表明,OLED的光电性能与空穴传输层的厚度密切相关,空穴传输层厚度为15nm时,OLED器件具有最低的启亮电压,最高的发光亮度和最大的发光效率.     

蓝光OLED的掺杂研究

采用蓝色发光材料ADN为主体发光材料、BAlq3为掺杂材料,通过改变BAlq3的掺杂浓度制备了结构为ITO/NPB/ADN:BAlq3/Alq3/Mg:Ag的一系列蓝光有机发光器件(OLED).研究了器件各有机层之间的能级匹配和BAlq3的掺杂浓度对载流子注入、传输、复合以及发光色纯度的影响.实验结果表明,空穴阻挡材料BAlq3的掺入显著影响OLED的电流密度、发光亮度、发光效率和发光光谱,当BAlq3的掺杂浓度为25%时,OLED的发光效率为1.0 lm/W,发光光谱的峰值为440 nm,色纯度为(0.18,0.15),未封装器件的半衰期为950小时,器件同时满足了高效率和高色纯度的要求.     

具有NPB:DPVBi掺杂层的有机白光器件的研究

制作了结构为ITO／NPB（50nm）／NPB;DPVBi（10：1,30nm）／Alqs（20nm）／LiF（1nm）／Al的有机白光器件。由于掺杂层NPB：DPVBi的引入,电子及空穴容易被DPVBi及NPB俘获,提高激子的复合,进一步提高监光的发光能力。发光区从Alq3的发光峰逐渐变为DPVBi的发光和NPB发光增强,从而发光峰值发生变化。该器件的最大亮度和效率分别为22V时4721cd／m^2和5V时0．80cd／A。     

阻挡层结构的蓝色有机发光二极管

制备了ITO／CuPc/NPB/TPBi/Alq3/MgAg有机发光二极 管,由于阻挡层TPBi对空穴的阻挡作用,器件的电致发光为NPB特征光谱,实现了蓝色发光。器件最大亮度和最大流明效率分别为3700cd/cm^2和0.78 lm/W,CIE色坐标为x=0.110 ,y=0.085,色度纯正。然而器件显现出较差的稳定。利用器件的能级结构,分析了器件的光学特性和影响稳定性的因素。     

Properties of non-doped organic light-emitting devices based on an ultrathin iridium complex phosphor layer

Organic light-emitting devices (OLEDs) were constructed with a structure of indium tin oxide (ITO)/N,N'-bis(naphthalen-1-yl)-N'-bis(phenyl)-benzidine (NPB) (50-xnm)/bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2'] iridium (acetylacetonate) [(t-bt)2Ir(acac)] (nm)/NPB (30nm)/Mg:Ag (200nm).A thin blue emission material of NPB was used as a separating layer,and the (t-bt)2Ir(acac) yellow phosphorescent dye was acted as an ultrathin light-emitting layer.TPBI acted as both hole-blocking and electron-transporting layer.By changing the location (x) and the thickness (d) of the phosphor dye,the variation of device performance were investigated.The results showed that all the devices had a turn-on voltage of 2.8V.In the case of d=0.2nm and x=5nm,the OLED had a maximum luminance of 18367cd/m2 and a maximum power efficiency of 5.3lm/W.The high performance is attributed to both direct charge carrier trapping of iridium phosphor dye and the thin NPB separation layer,which effectively confines the recombination zone of charge carriers.     

LiF作为电子注入层对OLEDs器件性能的影响

制造了两种OLEDs器件,它们的结构分别为:ITO/NPB(50 nm)/Alq3(65 nm)/Mg:Ag(10:1)(100 nm)/Ag(50 nm)and ITO/NPB(50 nm)/Alq3(65 nm)/LiF(x)/Al(100 nm).结果发现,在同样电压下,与Mg:Ag/Ag电极相比,插入LiF层可以明显提高器件的电流.当LiF厚度为1 nm时,器件性能最好.以Mg:Ag/Ag合金作为电极时的器件的最大亮度为8 450 cd/m2,而插入LiF层的器件最大亮度可达到14 700 cd/m2.此外,器件的发光效率也得到了明显的提高,在7 V时达到了最大为3.117 cd/mA.同时,当LiF厚度大于1 nm或小于1 nm时,器件性能都将会下降.     

Effect of different processing methods for the hole transporting layer on the performance of double layer organic light-emitting devices

The hole transporting layer （HTL） of organic light-emitting device （OLED） was processed by vacuum deposition and spin coating method, respectively, where N,N＇-biphenyl-N, N＇-bis（3-methylphenyl）- 1, l＇-biphenyl-4,4＇ -diamine （TPD） and poly （vinylcarbazole） （PVK） acted as the hole-transport materials. Tris-（8-hydroxyquinoline）- aluminum （Alq3） was utilized as both the light-emitting layer and the electron transporting layer. The basic structure of the device cell was： indium-tin-oxide （1TO）/PVK ： TPD/Alq3/Mg：Ag. The electroluminescent （EL） characteristics of devices were characterized. The results showed that the peak of EL spectra was located at 530 nm, which conformed to the characterizing spectrum of Alq3. Compared with using vacuum deposition method, the green emission with a maximum luminance up to 26135 cd/m2 could be achieved at a drive voltage of 15 V by selecting proper solvent using spin-coating technique, and its maximum lumi nance efficiency was 2.56 lm/W at a drive voltage of 5.5 V.     

Fabrication of large-scaled organic light emitting devices on the flexible substrates using low-pressure imprinting lithography

This paper demonstrates an approach to fabricate large-scaled (70 /spl times/70 mm) patterned organic light-emitting devices (ITO/CuPc/NPB/Alq3/LiF/Al) on the flexible polyethyleneterephthalate substrates using low-pressure imprinting lithography. The patterns of the pixel array were defined in crossed-strip style with anode patterned by imprinting techniques followed by wet chemical etching and cathode strips deposited using metal mask. The measured results were: The turn-on voltage of the device was 7.5 V; the luminous efficiency reached 1.13 lm/W (3.04 cd/A) at a luminance of 3.8 cd/m/sup 2/ and its maximum luminance was 2440 cd/m/sup 2/, which were comparable to the performances of the devices patterned by conventional photolithography.     

(t-bt)2Ir(acac)超薄层厚度对有机电致发光器件性能的影响

以新型铱配合物黄光磷光染料bis[2-(4-tertbutylphenyl)benzothiazolato-N,C2']iridium(acetylacetonate)[(tbt)2Ir(acac)]为超薄层,制备了结构为indium tin oxide(ITO)/N,N'-bis(naphthalen-1-yl)-N...     

磷光与荧光相结合的有机白光器件

首先制备了结构为ITO/m-MTDATA(30 nm)/NPB(20 nm)/CBP:FIrPIC(10%,30 nm)/5,6,11,12-tetraphenylnaphthacene(rubrene)(x nm/Bphen(40 nm)/LiF(0.8 nm)/Al的器件.此器件效率降低,为提高效率,我们又制备了另一器件,其结构为ITO/m-MTDATA(30 nm)/NPB(20 nm)/rubrene(0.2 nm)/CBP:FIrPIC(10%,30 nm)/Bphen(40 nm)/LiF(0.8 nm)/Al.此器件亮度效率及色坐标均有所改善.此器件的最大亮度为14 V时,10050 cd/m2,最大效率为8V时,4.59(cd/A),7 V时,1.89(lm/w).1000 cd/m2时的效率约为4.00 cd/A(10 V时,1.25 lm/w).当亮度由1354 cd/m2变到10050cd/m2时,色坐标由(0.33,0.37)变到(0.34,0.37).     

Effect of BCP ultrathin layer on the performance of organic light-emitting devices

Based on conventional double layer device, triple layer organic light-emitting diodes （OLEDs） with two heterostructures of indium-tin oxide （ITO）/N,N＇-diphenyl-N,N＇-bis（1-naphthyl）（1,1 ＇-biphenyl）-4,4＇-diamine（NPB）/2,9-dimethyl-4,7-diphenyl- 1,10-phenanthroline （BCP）/8-Hydroxyquinoline aluminum （Alq3）/Mg：Ag USing vacuum deposition method have been fabricated. The influence of different film thickness of BCP layer on the performance of OLEDs has been investigated. The results showed that when the thickness of the BCP layer film gradually varied from 0.1 nm to 4.0 nm, the electroluminescence （EL） spectra of the OLEDs shifted from green to greenish-blue to blue, and the BCP layer acted as the recombination region of charge carriers related to EL spectrum, enhancing the brightness and power efficiency. The power efficiency of OLEDs reached as high as 7.3 lm/W.