首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
D-π-A分子H-聚集体的电子光谱   总被引:2,自引:0,他引:2  
合成了具有强化给体和强电子受体的D-π-A分子5-(4-N,N-二甲氨基苯乙烯基)-(1H,3H)-2,4,6-嘧啶三酮(AB1)和5-(4-N,N-双十八烷基氨基苯乙烯基)-(1H,3H)-2,4,6-嘧啶三酮(AB18),并对其电子光谱进行了研究,AB18在环 聚集体的吸收光谱及AB1和AP18的表面光电压谱在450nm附近出现H-聚集体的谱带,比其在氯仿溶液中单体的ICT带蓝移了30nm左右,AB1和AB18固体及其高浓度的氯仿溶液分别在620nm和610nm附近出现来源于H-聚集体的激基缔合物的荧光,620nm带比单体红移3000cm^01 左右,还探讨具有强电子给体和受体的D-π-A分子间π-π相互作用.  相似文献   

2.
Three simple non-planar D-π-A TPA-based isomers (TPA-o, TPA-m, and TPA-p) were designed and synthesized via Suzuki reaction with higher yields. It was found that all of the three compounds had intramolecular charge transfer (ICT) properties resulting from electron donation from triphenylamine to the formyl moiety. Interestingly, TPA-based derivatives solids exhibited not only reversible mechanochromic behaviors, but structure-dependent emission properties. The solid emission studies illustrated that their fluorescence color could change reversibly between bright blue (455?nm), blue (445?nm), cyan (479?nm), and bright blue-green (497?nm), bright blue (460?nm), yellowish-green (511?nm) through grinding and dichloromethane (DCM) fuming treatment, giving the large spectral red-shifts of 42, 15, and 32?nm, respectively. The MFC activities of the three compounds are increased with the sequence of TPA-o (42?nm)?>?TPA-p (32?nm)?>?TPA-m (15?nm). The single crystal structure, powder X-ray diffraction (PXRD) and DSC studies indicated that the reversible phase change from crystalline to amorphous was responsible for MFC properties. This work demonstrated the feasibility of tuning the solid-state optical properties of fluorescent organic compounds by combining the simple alteration of chemical structure and the physical change of aggregate morphology under external stimuli. And these results will be of great help in understanding structure-property relationships of MFC mechanisms and designing new more MFC materials.  相似文献   

3.
D-π-A染料体系容易沿着π-共轭链发生分子内电子转移,使\其具有优良的二介非线性光学性质和光电转换性质;同时对它进行恰当的分子修饰能使其具有导电性和离子选择性,本文对D-π-A染料体系LB膜的发展现状及其应用领域进行了综述。重点介绍了在二阶非线性光学和光电转换等领域的应用研究。  相似文献   

4.
功能性有机染料在染料敏化太阳能电池领域具有重要的应用前景,电子给体、π共轭桥和电子受体(D-π-A)结构的染料是其中重要的组成类型.本文主要依据三苯胺和吲哚啉等取代苯胺为电子给体染料的结构设计,并结合本课题组的相关工作,综述了2008年以来此类D-π-A光敏染料的光电转换性能的研究进展.  相似文献   

5.
设计合成了3种主链相同、侧基不同的Donor(D)-π-Acceptor(A)型共轭聚合物:聚[(4,8-二辛氧基苯[1,2-b;3,4-b]二噻吩)-(9-(4-氰基苯基)-9H-咔唑)](PBDTCz-CN)、聚[(4,8-二辛氧基苯[1,2-b;3,4-b′]二噻吩)-(9-(4-醛基苯基)-9H-咔唑)](PBDTCz-CHO)和聚[(4,8-二辛氧基苯[1,2-b;3,4-b]二噻吩)-(9-(4-硝基苯基)-9H-咔唑)](PBDTCz-NO_2)。通过调变侧基上的受体基团,比较了氰基、醛基、硝基对聚合物光学和电学性能的影响,讨论了影响聚合物光电转换效率的主要因素。3种聚合物的光学带隙和线性吸收系数依次分别为2.32 eV,152.0 L/(g·cm);2.43 eV,58.5 L/(g·cm)和2.25 eV,85.5 L/(g·cm)。在这些聚合物中,彼此间的最高占据分子轨道(HOMO)能级差距很小,PBDTCz-NO_2的最低未占据分子轨道(LUMO)能级最低(-3.38eV)。在100 W/m~2模拟太阳光的照射下,基于这些聚合物的光伏器件(器件结构:ITO/PEDOT:PSS/Polymer:[70]PCBM(1:2)/Ca/A1)的光电转换效率分别为0.44%(PBDTCz-CN)、0.001 8%(PBDTCz-CHO)和0.23%(PBDTCz-NO_2)。低的光电转换效率主要归因于低的短路电流,而影响短路电流的主要原因有自身吸光性能的限制和弱的π-π堆砌作用。  相似文献   

6.
一种D-π-A型咔唑类衍生物的合成   总被引:1,自引:0,他引:1  
从咔唑,N,N-二甲基甲酰氨,溴己烷和丙二腈为原料,高效合成了双氰基功能性化合物--3-(2,2'-二氰基乙烯基)-N-己基咔唑(4),其结构经UV-Vis,荧光光谱,1H NMR,IR,MS及元素分析表征.考察了4的光学性质.  相似文献   

7.
Aggregation behavior of two amphiphilic D-π-A molecules bearing barbituric acid as both recogniton group and electron-drawing substituent , 5-(4-dodecyl oxybenzylidene)-(1H, 3H)-2,4,6-pyrimidine trione (PB12) and 5-(4-N,N-didodecyl aminobenzylidene)-(1H,3H)-2,4,6-pyrimidine trione (AB12) was studied by UV-visible, fluorescence, and surface voltaic spectroscopies (SPS). The experimental results indicate that PB12 tends to form J-aggregate and AB12 tends to form H-aggregate under increasing concentration. An intramolecular twisted charge transfer (TICT) emission around 500 nm is observed when J-aggregate is formed between PB12 molecules, and an excimer emission around 600 nm is observed when H-aggregate is formed between AB12 molecules.  相似文献   

8.
设计合成了6个带有烷基链的D-π-A型有机光敏染料应用于染料敏化太阳能电池. 发现长链烷基有利于电池开路光电压的提高. 利用脂肪酸共敏化可进一步提高染料分子的敏化效果, 且提高的程度与脂肪酸的链长有重要关系.  相似文献   

9.
以4'-(4-甲苯基)-2,2'∶6',2″-三联吡啶为电子受体(A)基元,通过Wittig反应引入电子给体(D)基元,合成了2个新的D-π-A型三联吡啶衍生物;研究了其单、双光子吸收荧光特性,并通过量子化学计算从结构角度进行了解释.目标产物的荧光量子产率(Ф)最高达到0.45,双光子吸收截面(δ2)最大达406 GM.  相似文献   

10.
本文分别以三苯胺、N-苯基咔唑和吲哚[3,2,1-jk]咔唑为给体,选择3,6-和2,7-位连接的咔唑为π-桥与氰基乙酸受体键连合成了两个系列共6个D-π-A型染料分子,研究了以它们为光敏剂的染料敏化太阳能电池器件的光伏性能.通过对比发现,给体单元相同的染料分子,以2,7-位连接的咔唑为π-桥时其共轭骨架的π-电子离域比3,6-位连接更好,因而其分子内电荷转移吸收明显变宽并增强,表现出更好的分子捕光能力,相应电池器件的短路电流密度(J_(sc))更大,展示了更高的光电转换效率;当π-桥相同时,给体单元由三苯胺依次变换为N-苯基咔唑和吲哚[3,2,1-jk]咔唑后,伴随苯环之间的直接键连其分子共平面性增强,氮原子上孤对电子参与共轭的程度增大,这虽有利于给体单元共轭骨架的π-电子离域,但会导致氮原子孤对电子参与的分子内推拉电子效应减弱,影响体系对太阳光的吸收利用,同时刚性共平面骨架加剧了分子间π-π堆积,引起染料聚集而加速载流子复合,从而影响其电池器件的开路电压(V_(oc))和J_(sc),不利于光伏性能的提升.  相似文献   

11.
采用偶氮反应合成了一系列对位分别连有不同吸电子和供电子功能基团的D-π-A共轭偶氮苯化合物,其结构经元素分析,IR,NMR,DSC等表征。  相似文献   

12.
Four organic donor-π-conjugated-acceptor (D-π-A) type II dyes with different thiophene linkers are reported for dye sensitized solar cells (DSSCs). For the first time, a donor (triphenylamine) was introduced in type II sensitizers, and 2-hydroxybenzonitrile as acceptor/anchoring moiety was covalently linked TiO2 particles. The dye LS203 in this series gives the best solar energy conversion efficiency of 3.4%, with Jsc = 7.4 mA cm−2, Voc = 0.67 V, FF = 0.69, the maximum IPCE value reaches 66.9%.  相似文献   

13.
以N,N-二羟乙基苯胺为原料,经3步反应制得中间体4-N,N-二乙巯基乙酸甲酯苯甲醛(4);4分别与对硝基苯乙氰和4-硝基苯甲基亚磷酸二乙酯经Wittig-Horner反应合成了两种新型羧酸酯衍生物(6和8),其结构经1H NMR,13C NMR,IR和MALDI-TOF-MS表征。运用UV-Vis和荧光光谱初步研究了6和8的光学性质。结果表明:6和8的最大吸收峰均位于440 nm和290 nm;6发生了明显淬灭,而8则显示了强烈的荧光。  相似文献   

14.
以对硝基甲苯为起始原料,与NBS经溴代反应制得对溴甲基硝基苯(2);2与亚磷酸三乙酯经取代反应得4-硝基苯基膦酸二乙酯(3);4-醛基苯基亚氨基二乙酸二乙醇与3或对硝基苯乙腈分别经Wittg-Homer反应和Knoevenagel缩合反应合成了两种新型芪类化合物(5和7),其结构经1H NMR,13C NMR,IR和ESI-MS表征.用UV-Vis和荧光光谱研究了5和7的光学性质.结果表明:5和7的最大吸收峰均位于410 nm;5的荧光发射峰位于529nm,较7红移26nm,发射强度提高129倍.  相似文献   

15.
以对硝基甲苯为起始原料,与NBS经溴代反应制得对溴甲基硝基苯(2);2与亚磷酸三乙酯经取代反应得4-硝基苯基膦酸二乙酯(3);4-醛基苯基亚氨基二乙酸二乙酯与3或对硝基苯乙腈分别经Wittig-Horner反应和Knoevenagel缩合反应合成了两种新型茋类化合物(5和7),其结构经1H NMR,13C NMR,IR和ESI-MS表征。用UV-Vis和荧光光谱研究了5和7的光学性质。结果表明:5和7的最大吸收峰均位于410 nm;5的荧光发射峰位于529 nm,较7红移26 nm,发射强度提高129倍。  相似文献   

16.
设计合成系列D-π-A偶氮苯酚探针,利用紫外-可见光谱对F~-、Cl~-、Br~-、I~-、HSO_4~-、H_2PO_4~-、NO_3~-和AcO~-阴离子进行识别,考察探针电子结构和空间位阻对F~-识别能力的影响。结果表明,在乙腈中P1~P4对F~-能选择性地识别,检测限达到0.10~0.63μmol·L~(-1)(1.90~11.97 ppm),探针分子与F~-形成的络合物共轭程度增大有利于对F~-识别,识别基团邻位取代基团空间位阻对F~-识别并不产生明显的影响。~1H NMR滴定表明识别机理为探针分子酚羟基与F~-通过氢键结合形成1∶1络合物。  相似文献   

17.
用固相法合成了具有D-π-A结构的N-{4-[4′-(N,N-二乙胺基)苯乙烯基]苯基}吡唑(3),其结构经1H NMR,IR,MS和元素分析表征.利用UV,单光子液体荧光光谱和固体荧光光谱探讨了3的光学性质.  相似文献   

18.
A new donor-π-acceptor (D-π-A) type isophorone dye was synthesized by the condensation reaction between 2-(3,5,5-trimethylcyclohex-2-enylidene)-malononitrile and indole-3-carboxaldehyde. The chemical structure of the dye was characterized by 1H NMR, EA and MS. A novel, chromogenic, fluorescent dye based on indol as donor unit and isophorone as acceptor unit displayed marked UV-visible absorption changes and highly selective fluorescence quenching in the presence of fluoride ion. The dye also exhibited sizeable colour changes when used as a pH-induced molecular switch and as a detector for volatile organic compounds. The absorption and fluorescent intensity of the dye can be reversibly selected by protonation/deprotonation of the amine moiety via control of intramolecular charge transfer (ICT), leading to a molecular switch with "on" and "off" states.  相似文献   

19.
Organic dyes with a D-π-A structure have drawn increasing attention as sensitizers in dye-sensitized solar cells (DSSCs), due to their rich photophysical properties, easy molecular tailoring, and low-cost production. This review mainly focuses on the relationship between dye structure and photovoltaic properties for organic dyes containing cyanoacrylic acid as both an anchor and an acceptor. This review also introduces different donors and π-conjugation units as building blocks for sensitizer synthesis.  相似文献   

20.
一种含D-π-A结构的新型化合物的合成与表征   总被引:3,自引:1,他引:2  
以咪唑和对氟苯甲醛为原料,合成了咪唑苯甲醛;咪唑苯甲醛与4-甲基吡啶反应得到一种新型的含D-π-A结构的化合物,其结构经UV,1H NMR,IR,MS和元素分析确证。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号