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81.
高分子电致发光显示器(PLED)是近几年来国际、国内的研究热点,取得了很大的进展,其中高分子化金属配合物是一类很有价值的功能材料。通过甲基丙烯酸甲酯(MMA)、苯乙烯(S)和含有8-羟基喹啉的单体共聚合成模板聚合物,再与氢氧化锂作用,实现了8-羟基喹啉锂配合物的高分子化,获得了一种能够溶解在普通的溶剂中的高相对分子质量的含喹啉锂配合物的发光聚合物,并利用元素分析、1H-NMR、FTIR、UV、PL光谱、DSC、TGA、GPC等方法对其结构和性能作了表征。紫外吸收和光致发光(PL)光谱说明合成共聚物的发光来自于Liq基团,引入的可聚合的链段以及共聚物中的甲基丙烯酸甲酯或苯乙烯链段,并没有影响发光波长的改变。亲核溶剂改变8-羟基喹啉金属配合物分子结构,使共聚物光谱明显红移20nm左右。 相似文献
82.
为了提高以TADF材料作为主体、天蓝色荧光材料作为客体的混合薄膜的OLED器件光电性能,我们调整了器件结构,使主体材料发挥其优势。制备了基本结构为ITO/NPB(40 nm)/DMAC-DPS∶x%BUBD-1(40 nm)/Bphen(30 nm)/LiF(0.5 nm)/Al的OLED器件。研究了主-客体材料在不同掺杂浓度下的OLED器件的光电特性。为了提高主体材料的利用率,在空穴传输层和发光层之间加入10 nm的DMAC-DPS作为间隔层;然后,在阳极和空穴传输层之间加入HAT-CN作为空穴注入层,形成HAT-CN/NPB结构的PN结,有效降低了器件的启亮电压(2.7 V)。测量了有无HAT-CN的单空穴器件的阻抗谱。结果表明,在最佳掺杂比例(2%)下,器件的外量子效率(EQE)达到4.92%,接近荧光OLED的EQE理论极限值;加入10 nm的DMAC-DPS作为间隔层,使得器件的EQE达到5.37%;HAT-CN/NPB结构的PN结有效地降低了器件的启亮电压(2.7 V),将OLED器件的EQE提高到5.76%;HAT-CN的加入提高了器件的空穴迁移率,降低了单空穴器件的阻抗。TADF材料作为主体材料在提高OLED器件的光电性能方面具有很大的潜力。 相似文献
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84.
In recent years, spatial self-phase modulation (SSPM) with two-dimensional (2D) materials has attracted the attention of many researchers as an emerging and ubiquitous nonlinear optical effect. In this review, the state of the art of 2D material-based SSPM is summarized. SSPM measures or tunes the nonlinearity of 2D materials, and it is also an effective approach to study the band structure of 2D materials. Several modified forms of SSPM, such as high-order, white-light-excited, vector field excited, and optically nonlinearly enhanced SSPM are also presented. Subsequently, the physical origin of the SSPM formation mechanism is compared and analyzed. Furthermore, the applications of SSPM with 2D materials, including passive photonic devices, generation of Bessel beams, and identifying the mode of the orbital angular momentum, are listed. Finally, several urgent problems of the SSPM with 2D materials, potential applications, and prospects for future development are presented. 相似文献
85.
简述超支化共轭聚合物光电活性材料研究进展,设计、合成了多种具有3-D立体结构的超支化共轭聚合物,研究了它们的结构与性能的关系及其在器件上的应用.实验结果表明,这种聚合物具有良好的溶解性,可成膜性和高的发光效率.可应用于发光二极管(LED),发光电化学池(LEC),光伏打电池等器件.这类化合物不仅可以作为发光材料,还可以通过修饰得到具有分子或离子识别、信息存储性能的特殊功能材料. 相似文献
86.
Fahime Bigdeli Christina T. Lollar Ali Morsali Hong‐Cai Zhou 《Angewandte Chemie (International ed. in English)》2020,59(12):4652-4669
In recent years, metal–organic frameworks (MOFs) have become an area of intense research interest because of their adjustable pores and nearly limitless structural diversity deriving from the design of different organic linkers and metal structural building units (SBUs). Among the recent great challenges for scientists include switchable MOFs and their corresponding applications. Switchable MOFs are a type of smart material that undergo distinct, reversible, chemical changes in their structure upon exposure to external stimuli, yielding interesting technological applicability. Although the process of switching shares similarities with flexibility, very limited studies have been devoted specifically to switching, while a fairly large amount of research and a number of Reviews have covered flexibility in MOFs. This Review focuses on the properties and general design of switchable MOFs. The switching activity has been delineated based on the cause of the switching: light, spin crossover (SCO), redox, temperature, and wettability. 相似文献
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88.
Yoshimichi Shimomura Prof. Dr. Kazunobu Igawa Dr. Shunsuke Sasaki Dr. Noritaka Sakakibara Prof. Dr. Raita Goseki Prof. Dr. Gen-ichi Konishi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201884
To design ultrabright fluorescent solid dyes, a crystal engineering strategy that enables monomeric emission by blocking intermolecular electronic interactions is required. We introduced propylene moieties to distyrylbenzene (DSB) as bridges between the phenyl rings either side of its C=C bonds. The bridged DSB derivatives formed compact crystals that emit colors similar to those of the same molecules in dilute solution, with high quantum yields. The introduction of flexible seven-membered rings to the DSB core produced moderate distortion and steric hindrance in the DSB π-plane. However, owing to this strategy, it was possible to control the molecular arrangement with almost no decrease in the crystal density, and intermolecular electronic interactions were suppressed. The bridged DSB crystal structure differs from other DSB derivative structures; thus, bridging affords access to novel crystalline systems. This design strategy has important implications in many fields and is more effective than the conventional photofunctional molecular crystal design strategies. 相似文献
89.
由于锂资源短缺,我们尝试使用三氧化钼作为钠离子储能装置负极材料。通过一种简单的方法合成了三氧化钼,使用XRD、SEM和TEM等测试手段对其物性进行了表征。利用三氧化钼作为有机系钠离子储能器件的负极材料,通过循环伏安和恒流充放电测试探讨了负极材料的储钠机理。以三氧化钼(MoO3)作为负极材料,活性炭(AC)和石墨(graphite)作为正极材料,组装成新型的电化学储能器件,研究了两种器件在1mol/L NaPF6的碳酸丙烯酯(PC)中的电化学性能。两种器件的电压范围分别为0~3.2V和0~3.5V,能量密度最高可分别达到31.6和53 Wh/kg,长循环性能远远优于AC/AC对称电容器。此种储能装置有望成为锂离子电池的一个很好的替代。 相似文献
90.
Hybrid Fibers Made of Molybdenum Disulfide,Reduced Graphene Oxide,and Multi‐Walled Carbon Nanotubes for Solid‐State,Flexible, Asymmetric Supercapacitors 下载免费PDF全文
Dr. Gengzhi Sun Xiao Zhang Rongzhou Lin Jian Yang Prof. Hua Zhang Prof. Peng Chen 《Angewandte Chemie (International ed. in English)》2015,54(15):4651-4656
One of challenges existing in fiber‐based supercapacitors is how to achieve high energy density without compromising their rate stability. Owing to their unique physical, electronic, and electrochemical properties, two‐dimensional (2D) nanomaterials, e.g., molybdenum disulfide (MoS2) and graphene, have attracted increasing research interest and been utilized as electrode materials in energy‐related applications. Herein, by incorporating MoS2 and reduced graphene oxide (rGO) nanosheets into a well‐aligned multi‐walled carbon nanotube (MWCNT) sheet followed by twisting, MoS2‐rGO/MWCNT and rGO/MWCNT fibers are fabricated, which can be used as the anode and cathode, respectively, for solid‐state, flexible, asymmetric supercapacitors. This fiber‐based asymmetric supercapacitor can operate in a wide potential window of 1.4 V with high Coulombic efficiency, good rate and cycling stability, and improved energy density. 相似文献