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<正>染料敏化纳米晶二氧化钛太阳能电池制备简单、成本低、光电转换效率高,已成为当前光电转换器件研究的热点之一.但目前还有许多制约染料敏化太阳能电池光电转换效率的问题有待解决.基于目前染料敏化太阳能电池在长波区采光不足的问题,本论文深入研究了在红光区域具有强吸光能力的方酸类染料在染料敏化太阳能电池中的应用,重点考察了方酸染料的结构对其光电转换性质的影响,并开辟了一种协同敏化新技术,还利用方酸染料的β-环糊精包合物实现了水溶液中氰根离子的高选择性检测.具体研究结果如下: 相似文献
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合成了不对称冠醚方酸碲碳菁染料和对称冠醚方酸碲碳菁染料,并探讨了对称冠醚方酸碲碳菁的合成方法及反应条件,提出了其可能的反应机理。 相似文献
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基于喹啉与苯胺衍生物不对称方酸菁染料的合成与光谱性质 总被引:1,自引:0,他引:1
设计合成了四个基于喹啉与苯胺衍生物的不对称方酸菁染料7a~7d,利用1HNMR,MS和元素分析对结构进行了表征.对中间体碘盐3a~3c的合成条件进行了探索,发现随着喹啉6位取代基吸电子能力的增强,亲核取代反应的活性降低,因此需要较为苛刻的条件.对不对称方酸菁的合成方法进行了系统研究,发现不对称方酸菁前体的接入方式是反应成败的关键,并对该不对称方酸菁的吸收光谱与光稳定性进行了系统研究.研究表明,染料的吸收半峰宽较宽,最大吸收随着溶剂极性的增加发生蓝移,表现为负溶剂化效应.光稳定性实验表明,染料的光稳定较好,且喹啉半体6位取代基吸电子能力的增加有利于染料光稳定性的增加.此外,苯胺半体氮上烷基链的长度对染料的光稳定性也有影响. 相似文献
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以苯并碲唑季铵碘盐为原料,将其与3-乙基-2-(β-乙酰苯胺)乙烯工噻唑磺化季铵盐在无水吡啶中回流,得到4个含碲不对称碳菁染料,上述季铵盐与方酸的反应不 般杂环碱,只能发生1:1缩合反应,缩合产物与苯并噻唑碘盐在正丁醇/吡啶中反应即得含碲不对称方酸菁染料,该法避免了通常制备不对称方酸菁所带来的分离纯化的困难,从而提供了制备不对称方酸碲菁染料的通用方法,研究了不对称碲碳菁的“Brooker偏差”,结 相似文献
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以吲哚啉季铵盐为原料, 分别采用两步法和固相法合成了3种水溶性不对称吲哚方酸菁染料. 两步法为将不同N-烷基取代的2,3,3-三甲基-3H-吲哚-5-磺酸季铵盐与方酸反应, 再与另一种吲哚啉季铵盐反应制备不对称菁染料. 固相法是用对氨基苯甲酸做桥连物, 将方酸化学键连到高分子固相载体聚乙二醇上, 然后与吲哚啉季铵盐杂环母核缩合制得带有固相高分子载体的半菁, 再与另一吲哚啉季铵盐杂环母核反应切掉载体, 合成不对称菁染料. 产品用C-18反相柱进行分离提纯, 通过核磁共振氢谱和质谱对产品结构进行了表征, 测试了产品的光谱性能. 比较而言, 固相法合成不对称染料效果更好, 产率接近传统两步法的二倍, 是一种更适合的合成水溶性不对称吲哚方酸菁染料的方法. 相似文献
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Deing KC Mayerhöffer U Würthner F Meerholz K 《Physical chemistry chemical physics : PCCP》2012,14(23):8328-8334
In this study, we investigated bulk-heterojunction solar cells composed of PC(61)BM and squaraine dyes with different donor subunits. Both, H- and J-aggregates, have been observed for the squaraine dyes in the mixture, even for the same dye depending on the annealing conditions of the blends. Supramolecular organization of the squaraine dyes noticeably affects solar cell performance. The J-aggregate exhibits a red-shift of the absorption maximum that results in a significant increase in the short-circuit current and decrease in the open-circuit voltage compared to the as-cast device. The H-aggregate shows a blue-shift in the absorption maximum and concomitantly only a moderate increase in the short-circuit current as well as an increase in the open-circuit voltage. The course of domain growth during annealing was monitored by local photocurrent mapping. 相似文献
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Gururaj M. ShivashimpiShyam S. Pandey Rie WatanabeNaotaka Fujikawa Yuhei OgomiYoshihiro Yamaguchi Shuzi Hayase 《Tetrahedron letters》2012,53(40):5437-5440
Aiming toward the development of far-red sensitive organic dyes, unsymmetrical squaraine dye bearing direct cyanoacrylate functionalized indole ring has been synthesized and characterized along with its utilization as photosensitizer for dye-sensitized solar cells. Upon dye-sensitized solar cell fabrication, this sensitizer exhibits its potentiality as a good far-red sensitive dye having photoconversion efficiency of 5.03% under the simulated solar irradiation at AM 1.5 conditions. This opens up further possibility to design efficient far-red sensitive dyes by judicious implementation of suitable donor moieties with extended π-conjugation. 相似文献
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Dr. Jared H. Delcamp Dr. Yanrong Shi Dr. Jun‐Ho Yum Dr. Tissa Sajoto Elisa Dell'Orto Dr. Stephen Barlow Dr. Mohammad K. Nazeeruddin Prof. Seth R. Marder Prof. Michael Grätzel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(5):1819-1827
A series of squaraine‐based sensitizers with various π bridges and anchors were prepared and examined in dye‐sensitized solar cells. The carboxylic anchor group was attached onto a squaraine dye through π bridges with and without an ethynyl spacer. DFT studies indicate that the LUMO is delocalized throughout the dyes, whilst the HOMO resides on the squaraine core. The dye that incorporates a 4,4‐di‐n‐hexyl‐cyclopentadithiophene group that is directly attached onto the π bridge, JD10 , exhibits the highest power conversion efficiency in a DSC; this result is attributed, in part, to the deaggregative properties that are associated with the gem‐di‐n‐hexyl substituents, which extend above and below the π‐conjugated dye plane. Dye JD10 demonstrates a power‐conversion efficiency of 7.3 % for liquid‐electrolyte dye‐sensitized solar cells and 7.9 % for cells that are co‐sensitized by another metal‐free dye, D35 , which substantially exceed the performance of any previously tested squaraine sensitizer. A panchromatic incident‐photon‐to‐current‐conversion efficiency curve is realized for this dye with an excellent short‐circuit current of 18.0 mA cm?2. This current is higher than that seen for other squaraine dyes, partially owing to a high molar absorptivity of >5 000 M ?1 cm?1 from 400 nm to the long‐wavelength onset of 724 nm for dye JD10 . 相似文献
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Dr. Ulrich Mayerhöffer Marcel Gsänger Dr. Matthias Stolte Benjamin Fimmel Prof. Dr. Frank Würthner 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(1):218-232
A broad series of more than 20 acceptor‐substituted squaraines was synthesized that feature different acceptor functionalities at the central squaraine four‐membered ring. The influence of these acceptor units on the reactivity of semisquaraine precursors and stability of the respective squaraines were explored. Thereby the dicyanovinyl group was found to be the most versatile acceptor group that enabled various modifications at the donor moiety of the squaraine scaffold, leading to an extended series of dicyanovinyl‐functionalized squaraines. The variation of donor units afforded a set of NIR fluorophores that cover a wavelength region from the visible at about 650 nm far into the NIR up to 920 nm with fluorescence quantum yields between 0.93 and 0.11 and outstanding optical brightness. This excellent optical property is related to a rigid molecular scaffold that is fixed in an all‐cis configuration by the additional dicyanovinyl acceptor unit. The change of the molecular symmetry from C2h to C2v upon functionalization of the squaraine core with dicyanovinyl acceptor group has been confirmed in solution by electro‐optical absorption (EOA) spectroscopy, revealing permanent ground‐state dipole moments μg in the range between 4.3 and 6.4 D. These dipole moments direct an antiparallel packing of the molecules in the solid state according to single‐crystal X‐ray analyses achieved for four dicyanovinyl‐functionalized squaraines. The structural properties, the EOA results, as well as the band shapes of the optical spectra indicate that these polymethine dyes are cyanine‐type chromophores. It is worth noting that the orientation of the dipole moment vectors is orthogonal to the orientation of the transition dipole moment vectors, which is an uncommon but characteristic feature of this rather novel class of polymethine dyes. With regard to applications of these dyes in organic solar cells, their redox properties were also studied by cyclic voltammetry. 相似文献
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Chemically converted graphene (CCG) was found to greatly enhance the fluorescence response of squaraine (SQ) dyes to bovine serum albumin (BSA). Addition of BSA to the SQ-CCG solution, where squaraine dyes absorbed on the CCG surface, raised the fluorescence intensity by as much as 80 fold. 相似文献
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A squaraine rotaxane endoperoxide with a truncated squaraine chromophore undergoes a cycloreversion reaction and emits green light that can be transferred to red acceptor dyes. The results demonstrate that chemiluminescence emission for squaraine rotaxane endoperoxides comes from the excited squaraine inside the rotaxane. 相似文献
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The design and development of novel squaraine dyes as sensitisers for photodynamic therapy (PDT) applications has grown tremendously in the last decade from the time when a squaraine dye was proposed to be a potential candidate, to-date when the use of such dyes have been demonstrated in animal models for skin cancer. This perspective article highlights the basic design, tuning of absorption, triplet excited state and two-photon absorption properties and recent developments of the squaraines as PDT sensitisers. 相似文献
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Alex S Basheer MC Arun KT Ramaiah D Das S 《The journal of physical chemistry. A》2007,111(17):3226-3230
The squaraine dye bis(2,4,6-trihydroxyphenyl)squaraine (SqH) was earlier reported to form J-type dimer aggregates in acetonitrile solutions at higher concentrations. Subsequent studies have suggested that concentration-dependent changes in the absorption spectrum of SqH in acetonitrile could be attributed to shifts in the acid-base equilibrium due to the presence of water as an impurity. In this work, we describe our studies on the effect of varying acid and dye concentration on the absorption spectra of the bromo and iodo substituted dyes, bis(3,5-dibromo-2,4,6-trihydroxyphenyl)squaraine (SqBr) and bis(3,5-diiodo-2,4,6-trihydroxyphenyl)squaraine (SqI). Analysis of the changes in the absorption spectra as a function of dye concentration and the nature of the solvent composition confirmed the formation of J-type dimer aggregates in aprotic solvents in this class of dyes. Further confirmation for the formation of the J-type dimer aggregates could be obtained by comparing the differences in the triplet excited state properties of the neutral and aggregated forms of the dyes using time-resolved spectroscopy. 相似文献
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Kulathinte M. Shafeekh Mohanannair S. Soumya Moochikkadavath A. Rahim Annie Abraham Suresh Das 《Photochemistry and photobiology》2014,90(3):585-595
Here, we report the synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, viz. bisbenzothiazolium squaraine dyes SQMI and SQDI with iodine in one and both benzothiazolium units, respectively, and an unsymmetrical squaraine dye ASQI containing iodinated benzothiazolium and aniline substituents. The diiodinated SQDI showed an anomalous trend in both fluorescence and triplet quantum yields over the monoiodinated SQMI, with SQDI showing higher fluorescence and lower triplet quantum yields compared to SQMI. Nanosecond laser flash photolysis of SQDI and SQMI indicated the formation of triplet excited states with quantum yield of 0.19 and 0.26, respectively. On photoirradiation, both the SQDI and SQMI generate singlet oxygen and it was observed that both dyes undergoing oxidation reactions with the singlet oxygen generated. ASQI which exhibited a lower triplet quantum yield of 0.06 was, however, stable and did not react with the singlet oxygen generated. In vitro cytotoxicity studies of these dyes in DLA live cells were performed using Trypan blue dye exclusion method and it reflect an order of cytotoxicity of SQDI>SQMI>ASQI. Intracellular generation of the ROS was confirmed by dichlorofluorescein assay after the in vitro PDT. 相似文献