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31.
Eric Chi‐Ho Kwok Dr. Mei‐Yee Chan Dr. Keith Man‐Chung Wong Dr. Wai Han Lam Prof. Dr. Vivian Wing‐Wah Yam 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(40):12244-12254
A series of platinum(II) alkynyl‐based sensitizers has been synthesized and found to show light‐to‐electricity conversion properties. These dyes were developed as sensitizers for the application in nanocrystalline TiO2 dye‐sensitized solar cells (DSSCs). Their photophysical and electrochemical properties were studied. The excited‐state property was probed using nanosecond transient absorption spectroscopy, which showed the formation of a charge‐separated state that arises from the intramolecular photoinduced charge transfer from the platinum(II) alkynylbithienylbenzothiadiazole moiety (donor) to the polypyridyl ligand (acceptor). A lifetime of 3.4 μs was observed for the charge‐separated state. A dye‐sensitized solar cell based on one of the complexes showed a short‐circuit photocurrent of 7.12 mA cm?2, an open circuit voltage of 780 mV, and a fill factor of 0.65, thus giving an overall power conversion efficiency of 3.6 %. 相似文献
32.
采用牛胰岛素作为模型多肽分子, 对几种结构相近的简单多酚的抗多肽淀粉样纤维化作用进行了研究. 结果表明, 邻苯二酚和对苯二酚对胰岛素纤维化具有抑制作用, 并通过形成醌中间体对多肽链进行修饰, 与对苯醌作用类似; 而苯酚和间二苯酚在相同条件下, 既不能修饰多肽也无抑制纤维化作用. 在无氧条件下, 邻苯二酚和对苯二酚对胰岛素纤维化的抑制作用明显降低, 说明酚化合物经氧化形成的醌中间体是其抗胰岛素纤维化的主要活性结构. 相似文献
33.
Juan‐José Cid Dr. Miguel García‐Iglesias Jun‐Ho Yum Dr. Amparo Forneli Josep Albero Eugenia Martínez‐Ferrero Dr. Purificación Vázquez Prof. Michael Grätzel Prof. Mohammad K. Nazeeruddin Prof. Emilio Palomares Prof. Tomás Torres Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(20):5130-5137
Let it shine! The impact of the anchoring group on photovoltaic performance by a series of phthalocyanine sensitisers (see figure) has been demonstrated.
34.
Jianfeng Lu Xiaobao Xu Zhihong Li Kun Cao Jin Cui Yibo Zhang Prof. Yan Shen Yi Li Prof. Jun Zhu Prof. Songyuan Dai Prof. Wei Chen Prof. Yibing Cheng Prof. Mingkui Wang 《化学:亚洲杂志》2013,8(5):956-962
Anchoring groups are extremely important in controlling the performance of dye‐sensitized solar cells (DSCs). The design and characterization of sensitizers with new anchoring groups, in particular non‐carboxylic acid groups, has become a recent focus of DSC research. Herein, new donor? π? acceptor zinc? porphyrin dyes with a pyridine ring as an anchoring group have been designed and synthesized for applications in DSCs. Photophysical and electrochemical investigations demonstrated that the pyridine ring worked effectively as an anchoring group for the porphyrin sensitizers. DSCs that were based on these new porphyrins showed an overall power‐conversion efficiency of about 4.0 % under full sunlight (AM 1.5G, 100 mW cm?2). 相似文献
35.
Dr. Pierre‐Antoine Bouit Magdalena Marszalek Dr. Robin Humphry‐Baker Dr. Rafael Viruela Prof. Dr. Enrique Ortí Dr. Shaik M. Zakeeruddin Prof. Dr. Michael Grätzel Dr. Juan Luis Delgado Prof. Dr. Nazario Martín 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(37):11621-11629
Two donor–acceptor molecular tweezers incorporating the 10‐(1,3‐dithiol‐2‐ylidene)anthracene unit as donor group and two cyanoacrylic units as accepting/anchoring groups are reported as metal‐free sensitizers for dye‐sensitized solar cells. By changing the phenyl spacer with 3,4‐ethylenedioxythiophene (EDOT) units, the absorption spectrum of the sensitizer is red‐shifted with a corresponding increase in the molar absorptivity. Density functional calculations confirmed the intramolecular charge‐transfer nature of the lowest‐energy absorption bands. The new dyes are highly distorted from planarity and are bound to the TiO2 surface through the two anchoring groups in a unidentate binding form. A power‐conversion efficiency of 3.7 % was obtained with a volatile CH3CN‐based electrolyte, under air mass 1.5 global sunlight. Photovoltage decay transients and ATR‐FTIR measurements allowed us to understand the photovoltaic performance, as well as the surface binding, of these new sensitizers. 相似文献
36.
Yeung ES 《Journal of chromatography. A》1999,830(2):4049-262
Capillary electrophoresis is known for its compatibility with biological materials and with small samples. It is an ideal tool for the study of single biological cells. Either whole cells or the material secreted from cells can be quantified. By continuously flowing a chemical stimulant over an immobilized cell inside the entrance of the capillary, one can even record the temporal progression of cellular secretion with sub-second resolution. The use of native fluorescence detection in such experiments provides a sensitive, rapid, non-intrusive and quantitative probe of important biomolecules such as catecholamines and proteins. 相似文献
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39.
Jinxiang He Fuling Guo Dr. Xin Li Wenjun Wu Jiabao Yang Prof. Dr. Jianli Hua 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(25):7903-7915
A series of new push–pull organic dyes ( BT‐I – VI ), incorporating electron‐withdrawing bithiazole with a thiophene, furan, benzene, or cyano moiety, as π spacer have been synthesized, characterized, and used as the sensitizers for dye‐sensitized solar cells (DSSCs). In comparison with the model compound T1 , these dyes containing a thiophene moiety between triphenylamine and bithiazole display enhanced spectral responses in the red portion of the solar spectrum. Electrochemical measurement data indicate that the HOMO and LUMO energy levels can be tuned by introducing different π spacers between the bithiazole moiety and cyanoacrylic acid acceptor. The incorporation of bithiazole substituted with two hexyl groups is highly beneficial to prevent close π–π aggregation, thus favorably suppressing charge recombination and intermolecular interaction. The overall conversion efficiencies of DSSCs based on bithiazole dyes are in the range of 3.58 to 7.51 %, in which BT‐I ‐based DSSCs showed the best photovoltaic performance: a maximum monochromatic incident photon‐to‐current conversion efficiency (IPCE) of 81.1 %, a short‐circuit photocurrent density (Jsc) of 15.69 mA cm?2, an open‐circuit photovoltage (Voc) of 778 mV, and a fill factor (ff) of 0.61, which correspond to an overall conversion efficiency of 7.51 % under standard global AM 1.5 solar light conditions. Most importantly, long‐term stability of the BT‐I – III ‐based DSSCs with ionic‐liquid electrolytes under 1000 h of light soaking was demonstrated and BT‐II with a furan moiety exhibited better photovoltaic performance of up to 5.75 % power conversion efficiency. 相似文献
40.
Ram B. Ambre Gao‐Fong Chang Manoj R. Zanwar Prof. Ching‐Fa Yao Prof. Eric Wei‐Guang Diau Dr. Chen‐Hsiung Hung 《化学:亚洲杂志》2013,8(9):2144-2153
A series of porphyrin sensitizers that featured two electron‐donating groups and dual anchoring groups that were connected through a porphine π‐bridging unit have been synthesized and successfully applied in dye‐sensitized solar cells (DSSCs). The presence of electron‐donating groups had a significant influence on their spectroscopic, electrochemical, and photovoltaic properties. Overall, the dual anchoring groups gave tunable electronic properties and stronger attachment to TiO2. These new dyes were readily synthesized in a minimum number of steps in gram‐scale quantities. Optical and electrochemical data confirmed the advantages of these dyes for use as sensitizers in DSSCs. Porphyrins with electron‐donating amino moieties provided improved charge separation and better charge‐injection efficiencies for the studied dual‐push–pull dyes. Attenuated total reflectance–Fourier‐transform infrared (ATR‐FTIR) and X‐ray photoelectron spectroscopy of the porphyrin dyes on TiO2 suggest that both p‐carboxyphenyl groups are attached onto TiO2, thereby resulting in strong attachment. Among these dyes, cis-Zn2BC2A , with two electron‐donating 3,6‐ditertbutyl‐phenyl‐carbazole groups and dual‐anchoring p‐carboxyphenyl groups, showed the highest efficiency of 4.07 %, with JSC=9.81 mA cm?2, VOC=0.63 V, and FF=66 %. Our results also indicated a better photostability of the studied dual‐anchored sensitizers compared to their mono‐anchored analogues under identical conditions. These results provide insight into the developments of a new generation of high‐efficiency and thermally stable porphyrin sensitizers. 相似文献