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121.
Jing Han Jin Mao Chen Xiao Wen Zhou Yuan Lin Jing Bo Zhang Jian Guang Jia Babasaheb Raghunath Sankapal 《Surface and interface analysis : SIA》2008,40(10):1393-1396
Solid‐state dye‐sensitized solar cells based on nanocrystalline TiO2 thin film with the structures TiO2/dye/CuI/Pt and TiO2/dye/In situ CuI/CuI/Pt were developed in order to compare the use of In situ deposited CuI (In situ CuI). Porosity of the screen‐printed nanoporous TiO2 thin film was enhanced by the addition of polystyrene balls. Evidence of decrease in interfacial resistance was observed by electrochemical impedance measurement for the device with In situ deposited CuI as compared to that without In situ deposited CuI as hole conductor. This was attributed to good interfacial contacts and better charge transfer between CuI and dye‐sensitized TiO2 nanoparticles, which resulted in the enhancement of power conversion efficiency from 0.058 to 1.01%. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
122.
Xue‐Hua ZHANG Yi‐Shan YAO Chao LI Wei‐Bo WANG Xue‐Xin CHENG Xue‐Song WANG Bao‐Wen ZHANG 《中国化学》2008,26(5):929-934
Three electron donor‐?? bridge‐electron acceptor (D‐π‐A) organic dyes bearing two carboxylic acid groups were applied to dye‐sensitized solar cells (DSSC) as sensitizers, in which one triphenylamine or modified triphenylamine and two rhodanine‐3‐acetic acid fragments act as D and A, respectively. It was found that the introduction of t‐butyl or methoxy group in the triphenylamine subunit could lead to more efficient photoinduced intramolecular charge transfer, thus improving the overall photoelectric conversion efficiency of the resultant DSSC. Under global AM 1.5 solar irradiation (73 mW·cm?2), the dye molecule based on methoxy‐substituted triphenylamine achieved the best photovoltaic performance: a short circuit photocurrent density (Jsc) of 12.63 mA·cm?2, an open circuit voltage (Voc) of 0.55 V, a fill factor (FF) of 0.62, corresponding to an overall efficiency (η) of 5.9%. 相似文献
123.
Fluorescent lanthanide complexes were synthesized using a non-phenolic analog of curcumin as the principal chromophoric chelating ligand. Sensitized, near-infrared fluorescence is observed in these complexes as a result of photo-excitation of the chromophoric ligands, population of the molecular triplet state, and transfer of energy to the emitting lanthanide ion. For the purpose of intra-molecular energy transfer, the triplet states of curcuminoid ligands are more favorably matched with the excited electronic states of neodymium and ytterbium ions than those associated with less conjugated β-diketonate ligands. Sensitization of fluorescence through an internal redox reaction, thought to occur in other ytterbium complexes, is predicted to be less probable under the present circumstances. 相似文献
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Organic dipolar compounds containing a 1,3‐indandione‐5,6‐dicarboxylic acid moiety as an electron acceptor group were examined for the feasibility of using as the light harvesting material in dye‐sensitized solar cells. Two compounds with triphenylamine donor moieties were synthesized by attaching it to 1,3‐indandione‐5,6‐dicarboxylic acid. The device made with these simple dyes achieved a quantum yield up to 2.5 %, which is comparable to the widely used dye made with cyanoacrylic acid. The spectroscopic properties of these compounds were analysed with the aid of theoretical models according to the time‐dependent density functional theory. 相似文献
126.
Kalle Lintinen Linda Storbacka Alexander Efimov Sami Hietala Risto Ahorinta Nikolai Tkachenko Helge Lemmetyinen 《Journal of polymer science. Part A, Polymer chemistry》2009,47(22):6095-6103
Cationic photopolymerization is a convenient in situ polymerization method for organic thin film preparation. In this work, the polymerization mechanisms is applied for highly viscous cross‐linking monomers, using tetra‐alkylepoxyporphyrin (TAEP) as a case study. By comparing the UV‐Vis spectra of the polymerized sample before and after the unreacted monomers have been dissolved, it is possible to estimate the polymerization yield. An IR spectrum of a reference thick film confirms full polymerization. Scanning fluorescence lifetime microscopy and AFM show the uniformity of the polymer. It was shown that photopolymerization is highly dependent on the substrate nature and requires at best case a 10 min illumination at 90 °C. Thermal polymerization of the same sample requires 10 min heating at 150 °C in dark. It was also shown that TAEP works as a self‐sensitizer for cationic photopolymerization. The proposed method is a mild and versatile technique for in situ preparation of thin polymeric films directly from chromophore monomers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6095–6103, 2009 相似文献
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SnO2 semiconductor nanowire is an extremely important technological material for use in nanophotonic and nanoelectronic devices. These semiconductor nanowires of desirable property can be achieved through a bottom-up approach to the controlled synthesis in a pure or doped state. Each of the synthetic methods offers materials with broad range structural, morphological, optical, and electrical properties. Selective doping of the SnO2 nanowires by normal, transition or inner transition elements offer a broad variation in the optical and electrical properties and are open for further theoretical exploration of the properties as well as necessary changes possible for the improvement of the material properties. The properties of SnO2 nanowires can be tuned either in the pure state by structural modification or doping during nanowire growth or after growth to meet most of the requirements. 相似文献
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