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排序方式: 共有2592条查询结果,搜索用时 15 毫秒
31.
Cationic and neutral mononuclear Cu(I) complexes, [Cu(PPh3)2(PmH)]BF4 (1a), [Cu(DPEphos) (PmH)]BF4 (2a), [Cu(Xantphos) (PmH)]BF4 (3a), [Cu(PPh3)2(Pm)] (1b), [Cu(DPEphos) (Pm)] (2b) and [Cu(Xantphos) (Pm)] (3b) (PPh3 = triphenylphosphine, DPEphos = bis(2-diphenylphosphinophenyl)ether, Xantphos = 9, 9-dimethyl-bis(diphenylphosphino)xanthenes, PmH = 2-(pyridin-2-yl)benzimidazole, Pm=(2-(Pyridin-2-yl)benzimidazolate), have been prepared and characterized by IR, 1H NMR, 13C NMR, 31P NMR, XRD, elemental analysis and X-ray crystal structure analysis. The structural analysis shows that each of Cu(I) complexes includes a tetrahedral [Cu(NN) (PP)]+ moiety, and temperature variation from 99 K to 298 K leads to the change of bonds lengths, angles and weak interactions. Meanwhile, theoretical calculations indicate that the differences between cationic and neutral Cu(I) complexes affect the composition of HOMO and LUMO orbitals, and the effect of temperature on Mülliken atomic charges is limited. Furthermore, neutral Cu(I) complexes 1b–3b show better luminescence in comparison to cationic Cu(I) complexes 1a-3a at room temperature, and temperature variations from 99 K to 298 K result in changing photoluminescence to some extent, which partly agrees with the related calculation results. In these cationic and neutral Cu(I) complexes, the maximum phosphorescent lifetime and quantum yield reach respectively 137 μs and 42% at room temperature. Moreover, cationic and neutral Cu(I) complexes are utilized to fabricate the monochromatic LEDs, showing favorable electroluminescence with the maximum EQE of 7.10%. 相似文献
32.
T.‐S. Kang B.S. Harrison M. Bouguettaya T.J. Foley J.M. Boncella K.S. Schanze J.R. Reynolds 《Advanced functional materials》2003,13(3):205-210
Near‐infrared‐emitting electroluminescent (EL) devices using blue‐light‐emitting polymers blended with the Yb complexes Yb(DBM)3phen (DBM = dibenzoylmethane), Yb(DNM)3phen (DNM = dinaphthoylmethane), and Yb(TPP)L(OEt) (L(OEt) = [(C5H5)Co{P(O)Et2}3]–) have been studied. EL devices composed of Yb(DNM)3phen blended with PPP‐OR11 showed enhanced near‐IR output at 977 nm when compared to those fabricated with Yb(DBM)3phen/PPP‐OR11 blends. The maximum near‐IR external efficiencies of the devices with Yb(DBM)3phen and Yb(DNM)3phen are, respectively, 7 × 10–5 (at 6 V and at 0.81 mA mm–2) and 4 × 10–4 (at 7 V, and 0.74 mA mm–2). The optimal blend composition for EL device performance consisted of PPP‐OR11 blended with 10–20 mol‐% Yb(DNM)3phen. A device fabricated using Yb‐(TPP)L(OEt)/PPP‐OR11 showed significantly enhanced near‐IR output efficiency, and future efforts will focus on devices fabricated using porphyrin‐based materials. 相似文献
33.
Europium Chromophores: Antiphotobleaching: A Type of Structurally Rigid Chromophore Ready for Constructing Highly Luminescent and Highly Photostable Europium Complexes (Adv. Funct. Mater. 13/2016) 下载免费PDF全文
Huibo Wei Zifeng Zhao Chen Wei Gang Yu Zhiwei Liu Bin Zhang Jiang Bian Zuqiang Bian Chunhui Huang 《Advanced functional materials》2016,26(13):2219-2219
34.
研究了镀镍液中微量铁的测定方法。采用5-溴水扬基荧光酮(5-BSAF)为显色剂。在pH5.0~6.0介质中,Fe(Ⅲ)与5-BSAF,CTMAB形成稳定的三元配合物。其最适测定波长在605nm。摩尔吸光系数ε_(605)=1.4×105,有色溶液2h内稳定不变,线性范围为0~7μg/25ml,线性相关系数γ=0.9997,加入回收率在97.7%~103%之间。高含量的各种镀液成分以及20余种物质不干扰测定。 相似文献
35.
Enhanced Electrochromism with Rapid Growth Layer‐by‐Layer Assembly of Polyelectrolyte Complexes 下载免费PDF全文
Mengqi Cui Wee Siang Ng Xu Wang Peter Darmawan Pooi See Lee 《Advanced functional materials》2015,25(3):401-408
In this work, a facile method to deposit fast growing electrochromic multilayer films with enhanced electrochemical properties using layer‐by‐layer (LbL) self‐assembly of complex polyelectrolyte is demonstrated. Two linear polymers, poly(acrylic acid) (PAA) and polyethylenimine (PEI), are used to formulate stable complexes under specific pH to prepare polyaniline (PANI)/PAA‐PEI multilayer films via LbL deposition. By introducing polymeric complexes as building blocks, [PANI/PAA‐PEI]n films grow much faster compared with [PANI/PAA]n films, which are deposited under the same condition. Unlike the compact [PANI/PAA]n films, [PANI/PAA‐PEI]n films exhibit porous structure that is beneficial to the electrochemical process and leads to improved electrochromic properties. An enhanced optical modulation of 30% is achieved with [PANI/PAA‐PEI]30 films at 630 nm compared with the lower optical modulation of 11% measured from [PANI/PAA]30 films. The switching time of [PANI/PAA‐PEI]30 films is only half of that of [PANI/PAA]30 films, which indicates a faster redox process. Utilizing polyelectrolyte complexes as building blocks is a promising approach to prepare fast growing LbL films for high performance electrochemical device applications. 相似文献
36.
Lei He Juan Qiao Lian Duan Guifang Dong Deqiang Zhang Liduo Wang Yong Qiu 《Advanced functional materials》2009,19(18):2950-2960
Using imidazole‐type ancillary ligands, a new class of cationic iridium complexes ( 1 – 6 ) is prepared, and photophysical and electrochemical studies and theoretical calculations are performed. Compared with the widely used bpy (2,2′‐bipyridine)‐type ancillary ligands, imidazole‐type ancillary ligands can be prepared and modified with ease, and are capable of blueshifting the emission spectra of cationic iridium complexes. By tuning the conjugation length of the ancillary ligands, blue‐green to red emitting cationic iridium complexes are obtained. Single‐layer light‐emitting electrochemical cells (LECs) based on cationic iridium complexes show blue‐green to red electroluminescence. High efficiencies of 8.4, 18.6, and 13.2 cd A?1 are achieved for the blue‐green‐emitting, yellow‐emitting, and orange‐emitting devices, respectively. By doping the red‐emitting complex into the blue‐green LEC, white LECs are realized, which give warm‐white light with Commission Internationale de L'Eclairage (CIE) coordinates of (0.42, 0.44) and color‐rendering indexes (CRI) of up to 81. The peak external quantum efficiency, current efficiency, and power efficiency of the white LECs reach 5.2%, 11.2 cd A?1, and 10 lm W?1, respectively, which are the highest for white LECs reported so far, and indicate the great potential for the use of these cationic iridium complexes in white LECs. 相似文献
37.
掺铕稀土配合物的光学树脂荧光光谱研究 总被引:2,自引:0,他引:2
报道了将多种稀土铕配合物复合于苯乙烯(ST)/甲基丙烯酸(HMA)的共聚体系,研究了含稀土配合物透明光学树脂的光学性能。发现其具有发光效率高,光谱呈现尖锐的线状谱带及相对于纯稀土配合物粉末来说掺有稀土配合物的光学树脂的发射产生光谱红移等特点。特别是用电子云重排效应(当中心稀土离子与不同配体结合时,其相同的J能级间的跃迁谱带位置略有移动的现象)解释了掺有稀土配合物的光学树脂发射光谱红移现象。并推断出在含稀土配合物复合于光学树脂后。稀土中心离子和配位原子间距离有所减小。 相似文献
38.
39.
40.
H.‐C. Su F.‐C. Fang T.‐Y. Hwu H.‐H. Hsieh H.‐F. Chen G.‐H. Lee S.‐M. Peng K.‐T. Wong C.‐C. Wu 《Advanced functional materials》2007,17(6):1019-1027
Highly efficient orange and green emission from single‐layered solid‐state light‐emitting electrochemical cells based on cationic transition‐metal complexes [Ir(ppy)2sb]PF6 and [Ir(dFppy)2sb]PF6 (where ppy is 2‐phenylpyridine, dFppy is 2‐(2,4‐difluorophenyl)pyridine, and sb is 4,5‐diaza‐9,9′‐spirobifluorene) is reported. Photoluminescence measurements show highly retained quantum yields for [Ir(ppy)2sb]PF6 and [Ir(dFppy)2 sb]PF6 in neat films (compared with quantum yields of these complexes dispersed in m‐bis(N‐carbazolyl)benzene films). The spiroconfigured sb ligands effectively enhance the steric hindrance of the complexes and reduce the self‐quenching effect. The devices that use single‐layered neat films of [Ir(ppy)2sb]PF6 and [Ir(dFppy)2sb]PF6 achieve high peak external quantum efficiencies and power efficiencies of 7.1 % and 22.6 lm W–1) at 2.5 V, and 7.1 % and 26.2 lm W–1 at 2.8 V, respectively. These efficiencies are among the highest reported for solid‐state light‐emitting electrochemical cells, and indicate that cationic transition‐metal complexes containing ligands with good steric hindrance are excellent candidates for highly efficient solid‐state electrochemical cells. 相似文献