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1.
《光电子技术》2023,43(4):317-322
量子点纯化工艺对铯铅溴(CsPbBr)钙钛矿量子点(PQDs)光学和电学性能影响极其重要。提出一种简单可行的复合配体钝化策略,用来修饰PQDs表面缺陷。溴化胍(GuaBr)和二癸基二甲基溴化铵(DDeAB)在纯化过程中被引入共同修饰钙钛矿量子点。这种配体钝化策略能够有效地抑制空位缺陷,并提高胶体稳定性和电学性能。最终,基于复合配体改性的量子点,绿色的PeLED器件具有低的性能滚降和15 786 cd/m的最大亮度。  相似文献   

2.
胶体量子点是一种半径接近于激子玻尔半径的新型优质光电材料,其特殊的尺寸效应使其能通过调整尺寸大小实现高纯度的三原色发光、连续可调的光谱以及宽色域。量子点特殊的核壳结构保证了其良好的光/热稳定性;同时,量子点还具有优异的可溶液处理特性,是显示领域研究的热门材料。基于量子点构筑的量子点发光二极管器件也一直被看作是有望取代有机发光二极管的极具潜力的技术。过去的几十年间,量子点发光二极管取得了巨大的成功和快速的发展,被看作是显示领域最具潜力的优质候选材料之一。因此,对量子点发光器件性能进行研究分析并优化,对于加快其商业市场化有很重要的意义。本文从量子点发光器件优化到大面积生产的角度总结了国内外研究者在构筑高效、稳定的面向显示应用的量子点发光器件的研究进展,并分析了其未来发展将面临的困难和挑战。  相似文献   

3.
量子点发光二极管(QD—LEDs)是将有机小分子OLED与可发光无机量子点(QD)结合起来而形成的一种新技术。量子点LED既具有聚合物的可溶性,容易制造的优点。同时还具有潜在的类似于磷光材料的高发光效率。  相似文献   

4.
采用室温合成法制备出CsPbBr3钙钛矿量子点,并采用乙酸乙酯对量子点进行了一次、二次和三次清洗,以控制其表面配体密度。然后,利用合成并经过清洗的钙钛矿量子点制备了结构为ITO/PEDOT∶PSS/PTAA/CsPbBr3 QD/TPBi/LiF/Al的电致发光二极管(QLED)。研究了经不同清洗次数的量子点材料制备的器件的光电性能。结果表明,清洗2次的量子点在电荷注入与溶液稳定性之间得到平衡,利用其制备的钙钛矿QLED获得了最大亮度为1405cd/m2、外量子效率为0.6%、色坐标为(0.127,0.559)的绿光发射。  相似文献   

5.
随着人们生活水平和社会经济的提升,对具有优良显色性和色彩再现力的液晶显示器的需求急剧增加。然而,商业使用的传统稀土掺杂的荧光粉转光层由于发射半峰宽太宽已经无法满足宽色域显示的需求,因此迫切需要开发一种新材料以实现宽色域显示。钙钛矿量子点玻璃因其优异的光学性能与卓越的稳定性被认为是背光显示器中传统荧光粉转光层的理想替代品,在显示行业具有广泛的应用前景。本文综述了钙钛矿量子点玻璃背光结构的应用方式,并对近年来钙钛矿量子点玻璃在背光应用的研究现状与发展中所面临的挑战进行了概括,最后对其进行了展望。  相似文献   

6.
郑文晨 《光电子技术》2023,43(4):287-292
利用LB(Langmuir‑Blodgett)转移印刷技术成功制备了分辨率为12 700 ppi的高性能QLED(Quantum Dot Light‑emitting Devices,量子点发光二极管)。通过该方法制备的超高分辨率红色QLED器件的为15.27%。此外还成功制备了为4.9%的超高分辨率白色QLED器件。本工作为下一代高分辨率显示器的实现提供了一种思路。  相似文献   

7.
全无机CsPbX3X=Cl、Br、I)钙钛矿量子点具有优异的发光性能,是一种极具应用潜力的新型显示材料及激光增益介质。本文制备了发光峰位于640nm的CsPbBr1.2I1.8红光量子点,在该量子点薄膜表面分别涂覆聚甲基丙烯酸甲酯(PMMA)、聚甲基丙烯酸异丁酯(PIBMA)、聚苯乙烯(PS)3种带不同功能基团的聚合物,制备了CsPbBr1.2I1.8/PMMA、CsPbBr1.2I1.8/PIBMA、CsPbBr1.2I1.8/PS复合薄膜,研究它们的放大自发辐射性能。结果表明,聚合物钝化一方面提升了量子点的水稳定性,另一方面,PMMA和PIBMA中的C̿O钝化了量子点表面未配位的Pb2+,增强了量子点薄膜的光致发光强度。进一步的,在532nm的纳秒激光泵浦下,CsPbBr1.2I1.8/PIBMA薄膜放大自发辐射阈值可低至81‍‍‍‍‍µJ·cm-2,稳定性也得到提升,展现了作为新型增益介质的潜力。  相似文献   

8.
量子点发光在显示器件中的应用   总被引:1,自引:2,他引:1  
介绍了量子点材料的发光原理、基本结构,以及量子点LED的特性、制备方法以及其在显示领域的最新进展。量子点LED由于具有发光纯度高、使用寿命长、可由溶液法制备等独特的优点,越来越受到人们的重视,成为显示领域新的研究热点。  相似文献   

9.
量子点是纳米科学与技术研究重要的组成部分,量子点器件又是纳米器件的发展方向之一.详细介绍了量子点的分类、量子点的主要制备方式、量子点特性的传统研究和微波类比仿真研究方法,系统论述了量子点器件的分类应用及噪声抑制.  相似文献   

10.
硅基光源是实现硅基集成光电子芯片的核心器件,虽然近年来国内外已经取得多项重要成果,但适合于下一代大规模光电集成芯片的小尺寸、低功耗、工艺兼容的高效硅基发光器件仍然缺乏。文章介绍了基于嵌入光学微腔中的锗量子点实现硅基发光器件方面的研究成果,通过将分子束外延生长的锗自组装量子点嵌入硅光子晶体微腔中,实现了室温下处于通信波段的共振发光。通过在图形化衬底上生长实现锗量子点的定位,并精确嵌入光子晶体微腔中,实现了基于锗单量子点的硅基发光器件。  相似文献   

11.
    
Novel light emitting electrochemical cells (LECs) are fabricated using CdSe‐CdS (core‐shell) quantum dots (QDs) of tuned size and emission blended with polyvinylcarbazole (PVK) and the ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIM‐PF6). The performances of cells constructed using sequential device layers of indium tin oxide (ITO), poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS), the QD/PVK/IL active layer, and Al are evaluated. Only color saturated electroluminescence from the QDs is observed, without any other emissions from the polymer host or the electrolyte. Blue, green, and red QD‐LECs are prepared. The maximum brightness (≈1000 cd m‐2) and current efficiency (1.9 cd A‐1) are comparable to polymer LECs and multilayer QD‐LEDs. White‐light QD‐LECs with Commission Internationale d'Eclairage (CIE) coordinates (0.33, 0.33) are prepared by tuning the mass ratio of R:G:B QDs in the active layer and voltage applied. Transparent QD‐LECs fabricated using transparent silver nanowire (AgNW) composites as the cathode yield an average transmittance greater than 88% over the visible range. Flexible devices are demonstrated by replacing the glass substrates with polyethylene terephthalate (PET).  相似文献   

12.
    
The fabrication of bio‐hybrid functional films is demonstrated by applying a materials assembly technique. Based on the hierarchical structures of silk fibroin materials, functional molecular/materials, i.e., quantum dots (QDs), can be fixed to amino acid groups in silk fibroin films. It follows that white‐light‐emitting QD silk hybrid films are obtained by hydrogen bond molecular recognition to the –COO groups functionalized to blue luminescent ZnSe (5.2 nm) and yellow luminescent CdTe (4.1 nm) QDs in a molar ratio of 30:1 of ZnSe to CdTe QDs. Simultaneously, a systematic blue shift in the emission peak is observed from the QD solution to QDs silk fibroin films. The significant blue shift hints the appearance of the strong interaction between QDs and silk fibroins, which causes strong white‐light‐emitting uniform silk films. The molecular recognized interactions are confirmed by high resolution transmission electron microscopy, field scanning electron microscope, and attenuated total internal reflectance Fourier transform infrared spectroscopy. The QD silk films show unique advantages, including simple preparation, tunable white‐light emission, easy manipulation, and low fabrication costs, which make it a promising candidate for multicomponent optodevices.  相似文献   

13.
    
Recently developed CsPbX3 (X = Cl, Br, and I) perovskite quantum dots (QDs) hold great potential for various applications owing to their superior optical properties, such as tunable emissions, high quantum efficiency, and narrow linewidths. However, poor stability under ambient conditions and spontaneous ion exchange among QDs hinder their application, for example, as phosphors in white‐light‐emitting diodes (WLEDs). Here, a facile two‐step synthesis procedure is reported for luminescent and color‐tunable CsPbX3–zeolite‐Y composite phosphors, where perovskite QDs are encapsulated in the porous zeolite matrix. First zeolite‐Y is infused with Cs+ ions by ion exchange from an aqueous solution and then forms CsPbX3 QDs by diffusion and reaction with an organic solution of PbX2. The zeolite encapsulation reduces degradation and improves the stability of the QDs under strong illumination. A WLED is fabricated using the resulting microscale composites, with Commission Internationale de I'Eclairage (CIE) color coordinates (0.38, 0.37) and achieving 114% of National Television Standards Committee (NTSC) and 85% of the ITU‐R Recommendation BT.2020 (Rec.2020) coverage.  相似文献   

14.
    
Organometal halide perovskites quantum dots (OHP‐QDs) with bright, color‐tunable, and narrow‐band photoluminescence have significant advantages in display, lighting, and laser applications. Due to sparse concentrations and difficulties in the enrichment of OHP‐QDs, production of large‐area uniform films of OHP‐QDs is a challenging task, which largely impedes their use in electroluminescence devices. Here, a simple dip‐coating method has been reported to effectively fabricate large‐area uniform films of OHP‐QDs. Using this technique, multicolor OHP‐QDs light‐emitting diodes (OQ‐LEDs) emitting in blue, blue‐green, green, orange, and red color have been successfully produced by simply tuning the halide composition or size of QDs. The blue, green, and red OQ‐LEDs exhibited, respectively, a maximum luminance of 2673, 2398, and 986 cd m?2 at a current efficiency of 4.01, 3.72, and 1.52 cd A?1, and an external quantum efficiency of 1.38%, 1.06%, and 0.53%, which are much better than most LEDs based on OHP films. The packaged OQ‐LEDs show long‐term stability in air (humidity ≈50%) for at least 7 d. The results demonstrate the great potential of the dip‐coating method to fabricate large‐area uniform films for various QDs. The high‐efficiency OQ‐LEDs also demonstrate the promising potential of OHP‐QDs for low‐cost display, lighting, and optical communication applications.  相似文献   

15.
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Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-based QDs.How-ever,enormous attention has been paid to how to narrow their broadband spectra,ignoring the application advantages of the broadband emission.In this work,the AIGS QDs with controllable broad green-red dual-emission are first reported,which is achieved through adjusting the size distribution of QDs by controlling the nucleation and growth of AIGS crys-tals.Resultantly,the AIGS QDs exhibit broad dual-emission at green-and red-band evidenced by photoluminescence(PL)spectra,and the PL relative intensity and peak position can be finely adjusted.Furthermore,the dual-emission is the intrinsic characteristics from the difference in confinement effect of large particles and tiny particles confirmed by temper-ature-dependent PL spectra.Accordingly,the AIGS QDs(the size consists of 17 nm and 3.7 nm)with 530 nm and 630 nm emission could successfully be synthesized at 220 ℃.By combining the blue light-emitting diode(LED)chips and dual-emission AIGS QDs,the constructed white light-emitting devices(WLEDs)exhibit a continuous and broad spec-trum like natural sunlight with the Commission Internationale de I'Eclairage(CIE)chromaticity coordinates of(0.33,0.31),a correlated color temperature(CCT)of 5425 K,color rendering index(CRI)of 90,and luminous efficacy of radiation(LER)of 129 Im/W,which indicates that the AIGS QDs have huge potential for lighting applications.  相似文献   

16.
    
Spin optoelectronics is an indispensable key for the future development of spintronics. In conventional spin light emitting diodes (LEDs), spin-polarized carrier pairs are injected electrically into the light emitting layer and create circularly polarized light (CPL). Generally, spin-polarized carriers are accomplished using ferromagnetic contacts or applying an external magnetic field, which will produce several drawbacks, including low temperature operation, low spin-polarized carriers injection efficiency, etc. To circumvent the existing shortcomings, here, an alternative approach is proposed and achieves spin-polarized LEDs at room temperature based on quantum dots (QDs)/chiral metal-organic framework heterojunction without using ferromagnetic contacts or magnetic fields. The spin-polarized injected layer composed of self-assembled monolayer (SAM)/Chiral-MOF ([Sr(9,10-adc)(DMAc)2]n)) film, which produces spin-polarized holes with spin orientation, determining the polarization and strength of circularly polarized electroluminescence (CP-EL). The spin-QLED emits CP-EL at a rate of 12.24% efficiency, which provides an excellent alternative to generate new functionality for conventional QLEDs. The approach is anticipated to be very useful, enabling to offer a general methodology for generating not yet realized spin optoelectronic devices.  相似文献   

17.
    
Graphene quantum dots (GQDs) with white fluorescence are synthesized by a microwave‐assisted hydrothermal method using graphite as the precursor. A solution‐processed white‐light‐emitting diode (WLED) is fabricated using the as‐prepared white fluorescent GQDs (white‐light‐emitting graphene quantum dots, WGQDs) doped 4,4‐bis(carbazol‐9‐yl)biphenyl as the emissive layer. White‐light emission is obtained from the WLED with 10 wt% doping concentration of WGQDs, which shows a luminance of 200 cd m?2 at the applied voltage of 11–14 V. Importantly, an external quantum efficiency of 0.2% is achieved, which is the highest among all the reported WLED based on GQDs or carbon dots. The results demonstrate that WGQDs as a novel phosphor may open up a new avenue to develop the environmentally friendly WLEDs for practical application in solid‐state lighting.  相似文献   

18.
基于CdSe/ZnS和Alq3的白光量子点LED的研究   总被引:4,自引:4,他引:0  
采用CdSe/ZnS红光量子点(QD),利用旋涂和真 空蒸镀工艺制备了结构为ITO/TPD+PVK/QDs/Alq3/LiF/Al的量 子点发光器件(QD-LED),并对器件的发光性能做了测试。研究了ITO表面处理、TPD空穴 传输层和QD发光层的厚 度对QD-LED性能的影响,并通过调整QD发光层和Alq3电子传输层的 厚度,制备了可用于照明 的白光QD-LED。实验结果表明,ITO的表面处理可有效降低器件的开启电压,开启 电压从9V降到7V左右; TPD空穴传输层和QD发光层的厚度对器件的电流密度和发光亮度有较大的影响,而Alq3电 子传输层和QD发光层 的合理配比可以混合出较高色温的白光。通过优化器件各参数,当TPD和PVK质量比为5∶1、QD度为1.0mg/ml和 Alq3厚为60nm时,制备的器件在15V电压 时发光效率达到了1500c d/m2,色坐标为(0.3628,0.3796) ,显色指数为88.1。  相似文献   

19.
液晶显示是目前广泛应用的显示技术,然而常用的LED背光荧光粉的宽光谱特点限制了其色彩显示能力和总流明效率的进一步提升。量子点具有窄发射光谱和高荧光效率等优势,为提高液晶显示色彩品质和感知亮度提供了新技术路线。本文介绍了量子点液晶显示(QD-LCD)应用的结构设计和材料体系,探讨了量子点应用存在的材料稳定性、背光设计难度和制备成本等问题。针对液晶显示应用的低成本、低毒性和易集成需求,讨论了钙钛矿量子点的应用前景,特别是进一步扩展量子点适用性的解决方案,如彩膜透过率光谱交叉、偏振片的能量损失等问题。  相似文献   

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