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1.
卟啉类光敏剂在染料敏化太阳能电池中的应用   总被引:5,自引:0,他引:5  
染料敏化太阳能电池结合了染料光敏剂和无机半导体的优势,具有较宽的光谱响应范围,制造工艺简单、成本较低,对环境友好,应用前景广阔,因而备受人们的关注。本文以卟啉配合物为主线,介绍光敏太阳能电池的基本构造和光电原理,从改善电池性能的角度,综述了各种卟啉类光敏剂在染料太阳能电池中的应用,讨论了卟啉配合物及其超分子结构对光电转化率的影响机理。  相似文献   
2.
三碳菁染料的研究   总被引:1,自引:0,他引:1  
姚祖光  方希 《应用化学》1991,8(6):82-84
三碳菁染料的吸收在近红外区,可用作卤化银感光材料的红外增感染料,近年来在红外激光染料和光信息记录介质等方面也得到了开发及应用。在多甲川链上引入桥环可提高染料的稳定性。本文合成了9种含芳胺基取代的桥链三碳菁,讨论染料结构与其增感性能关系。  相似文献   
3.
Thermal lens spectrometry (TLS) is an excellent tool for trace analysis1. TLS allows the detection of absorbances of 10-7~10-8, concentration of ≈ 10-11 mol稬-1 and the analysis of 10-15 L volumes with ≈10-2 absorbing molecules2. Kinetic analysis is playing an increasingly important part in modern analytical chemistry. Therefore, TLS shows much promise in combination with kinetic analysis. However, there are few data on TLS applications in kinetic analysis method so far3~4. A ne…  相似文献   
4.
双(6-溴代-9-乙基-咔唑-3-基)甲苯基碘盐的合成   总被引:1,自引:1,他引:1  
双(9-乙基-咔唑-3-基)甲苯基碘盐是一种性能优良的有机光电导体增感剂.本文合成了双(6-溴代-9-乙基-咔唑-3-基)甲苯基碘盐,其分子结构通过红外、核磁、质谱和元素分析得到证实.初步实验表明该染料具有较宽范围的光谱响应,与聚 N-乙烯基咔唑(简称 PVK)相配合具有优良的光敏性能.  相似文献   
5.
The photochemistry of the vitamin D family and their precursors has been the subject of extensive studies for many years1-4. Most of the studies focus on the photoisomer- ization of 7-dehydrocholesterol and that of tachysterol to previtamin D3, which is of commercial importance in the synthesis of vitamin D34, 5. Recently the cis/trans isomerization of vitamin D analogs (Scheme 1) draws attention because of its importance in the synthesis of hydroxylated vitamin D metabolites6. However, o…  相似文献   
6.
Amphiphilic polypyridyl mthenium(Ⅱ) complex cis-di(isothiocyanato)(4,4'-di-tert-butyl-2,2'-bipyridyl)(4,4'- dicarboxy-2,2'-bipyridyl)ruthenium(Ⅱ)(K005) has been synthesized and characterized by cyclic voltammetry, ^1H NMR, UV-Vis, and FT-IR spectroscopies. The sensitizer sensitizes TiO2 over a notably broad spectral range due to its intense metal-to-ligand charge-transfer (MLCT) bands at 537 and 418 nm. The photophysical and photochemical studies of K005 were contrasted with those of cis-Ru(dcbpy)2(NCS)2, known as the N3 dye, and the amphiphilic ruthenium(Ⅱ) dye Z907. A reversible couple at E1/2=0.725 V vs. saturated calomel electrode (SCE) with a separation of 0.08 V between the anodic and cathodic peaks, was observed due to the Ru^Ⅱ/Ⅲ couple by cyclic voltammetry. Furthermore, this amphiphilic ruthenium complex was successfully used as sensitizers for dye-sensitized solar cells with the efficiency of 3.72% at the 100 mW·cm^-2 irradiance of air mass 1.5 simulated sunlight without optimization of TiO2 films and the electrolyte.  相似文献   
7.
New quinoxaline-based organic sensitizer bearing di-anchoring group for dye-sensitized solar cells (DSSCs) was synthesized from diethyl 4,5-diaminophthaltate, in which was prepared under mild condition by using Takehito’s method. The synthesized sensitizer was compared with mono-anchoring sensitizer through absorption spectra, emission spectra, J-V curve, and IPCE spectra, indicating the di-anchoring group leads to a noticeable improvement of Jsc value owing to more efficient intramolecular charge transfer and channel number increment.  相似文献   
8.
Structure–activity relationship (SAR) models are recognized as powerful tools to predict the toxicologic potential of new or untested chemicals and also provide insight into possible mechanisms of toxicity. Models have been based on physicochemical attributes and structural features of chemicals. We describe herein the development of a new SAR modeling algorithm called cat-SAR that is capable of analyzing and predicting chemical activity from divergent biological response data. The cat-SAR program develops chemical fragment-based SAR models from categorical biological response data (e.g. toxicologically active and inactive compounds). The database selected for model development was a published set of chemicals documented to cause respiratory hypersensitivity in humans. Two models were generated that differed only in that one model included explicate hydrogen containing fragments. The predictive abilities of the models were tested using leave-one-out cross-validation tests. One model had a sensitivity of 0.94 and specificity of 0.87 yielding an overall correct prediction of 91%. The second model had a sensitivity of 0.89, specificity of 0.95 and overall correct prediction of 92%. The demonstrated predictive capabilities of the cat-SAR approach, together with its modeling flexibility and design transparency, suggest the potential for its widespread applicability to toxicity prediction and for deriving mechanistic insight into toxicologic effects.  相似文献   
9.
近年来,高性能荧光有机电致发光器件(FOLEDs)的开发受到了广泛关注。由于荧光材料仅能利用25%的单重态激子辐射发光,FOLEDs的外量子效率(EQE)理论极限为5%。通过能量转移,充分利用主体分子的单重态与三重态激子敏化荧光客体发光,可以提高激子利用率。目前敏化型FOLEDs(SFOLEDs)的最高EQE已达26.1%。本文详细介绍了SFOLEDs的敏化原理和机制,并根据敏化机制的不同,系统地总结了热活化延迟荧光敏化、激基复合物敏化、三重态湮灭敏化和局域电荷转移杂化激发态(HLCT)敏化等各类SFOLEDs的材料与器件结构特点及其研究进展。最后本综述对该类器件的研究前景进行了展望,期待吸引更多专业的研究人员的研究兴趣,进而推动该领域的发展。  相似文献   
10.
It is highly desired to maximize the use of solar light by developing broadband-light-responsive H2 production system in the field of photocatalysis. Herein, a novel PbS/(Pt–TiO2) nanocomposite with efficient and unusual broadband-light-driven H2 production feature is constructed by using infrared-bandgap PbS nanocrystals as sensitizer of Pt-loaded ultrafine anatase TiO2 nanotubes (Pt–TiO2). After optimizing the component ratio, the resultant PbS/(Pt–TiO2) nanocomposite delivers a H2 production activity of 813 and 186 μmol h?1 under ultraviolet (UV)-visible (Vis)-near-infrared (NIR) and Vis-NIR light irradiation, respectively. Moreover, an apparent quantum yield of 38.6%, 26.2%, 2.43%, 3.21%, 2.17%, 0.36%, 0.11% and 0.01% can be attained from the PbS/(Pt–TiO2) nanocomposite illuminated at 350, 420, 550, 700, 760, 850, 950 and 1064 nm monochromatic light, respectively. The intimate interfacial contacts in the PbS nanocrystals decorated ultrafine TiO2 nanotubes, which serve as the support and electron acceptor of PbS nanocrystals, can effectively promote the photoexcited hot electrons transferring from PbS nanocrystals to TiO2 nanotubes before the thermalization losses, and thus causing the efficient Vis-NIR-light-responsive H2 production activity of the PbS/(Pt–TiO2) nanocomposite. These results provide an intriguing application of infrared-bandgap materials to exploit the low-energy photons of the solar light for constructing efficient and unusual broadband-responsive H2 production system.  相似文献   
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