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Hierarchically Structured ZnO Nanorods as an Efficient Photoanode for Dye‐Sensitized Solar Cells 下载免费PDF全文
Dr. Wenqin Peng Dr. Liyuan Han Dr. Zhengming Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(27):8483-8487
Hierarchical ZnO nanorods composed of interconnected nanoparticles, which were synthesized by controlling precursor concentrations in a solvothermally assisted process, were exploited as photoanodes in dye‐sensitized solar cells (DSCs). The as‐prepared hierarchical nanorods showed greatly enhanced light scattering compared to ZnO nanoparticles for boosting light harvesting while maintaining sufficient dye‐adsorption capability. The charge‐transfer characteristics were studied by electrochemical impedance measurements, and reduced electron recombination and longer electron lifetime were observed for the ZnO nanorods. Photovoltaic characterization demonstrated that DSCs utilizing the hierarchical nanorods significantly improved the overall conversion efficiency by 34 % compared to nanoparticle‐based DSCs. 相似文献
214.
Sha Zhou Tao Yan Sha Zhou Xuewen Hua Baolei Wang Yucheng Gu Lixia Xiong Yongqiang Li Zhengming Li 《中国化学》2014,32(7):567-572
Due to a novel mode action, low toxicity to mammals and low residue characteristics, phthalic acid diamides have aroused considerable interests in agricultural chemistry. With introduction of N‐cyano, N‐trifluoroacetyl, N‐carbamoylsulfiliminyl and sulfoximinyl substituents into phthalamides, 12 novel derivatives containing trifluoromethyl moiety were designed and synthesized. All title compounds were characterized by 1H NMR and high‐resolution mass spectrometry. The preliminary results of biological activity assessment indicated that some title compounds exhibited moderate to good insecticidal activities against oriental armyworm (Pseudaletia separata Walker). In particular, Va gave higher activity against oriental armyworm and diamondback moth. The present work reported that the new trifluoromethylated diamides incorporating N‐trifluoroacetylsulfoximinyl moieties are potential lead compounds for further structure optimization, providing some insight into the relating structure‐activity relationship. 相似文献
215.
Peng W Wang Z Yoshizawa N Hatori H Hirotsu T 《Chemical communications (Cambridge, England)》2008,(36):4348-4350
A novel composite composed of tubular titanate-two dimensionally deposited carbon nanosheets was prepared with carbon nanosheets as templates through intercalation and hydrothermal treatment; this nanotube-based composite and its calcined products exhibit both excellent adsorptivity and high photocatalytic activity toward organic molecules. 相似文献
216.
以取代磺酰肼和糖基异硫氰酸酯反应,生成8种1-取代磺酰基-4-全乙酰糖基氨基硫脲,然后在ClCH2CHO/CH3COONa/DMF条件下关环,区域选择性地合成了一系列新型2-取代磺酰基亚肼基-3-全乙酰糖基-2,3-二氢噻唑.化合物3e的1H-13CHMBC谱图表明1-取代磺酰基-4-全乙酰糖基氨基硫脲与氯乙醛的缩合反应关环位置为氨基硫脲的N-4,而非N-2.所有新化合物的结构均经过1HNMR,13CNMR和元素分析确证,生物活性初步测定结果表明该类二氢噻唑化合物具有一定的除草活性. 相似文献
217.
改良的Wittig 反应 总被引:1,自引:0,他引:1
本文对改良的Wittig反应进行了综述,并讨论了膦酸酯类与羰基化合物反应的各种机理。还介绍了此反应在有机合成上的应用。 相似文献
218.
Shiyue Xu Minjian Zhong Liming YuHangde Chen Zhengming HeJincang Zhang 《Journal of magnetism and magnetic materials》2006
FCC (Fe55Ni45)1−xCx supersaturated solid solution was prepared in a wide concentration range (0?x?0.9) by mechanical alloying of nanocrystalline Fe55Ni45 with graphite. The lattice constant of Fe55Ni45 increases linearly with increasing carbon content up to x=0.25. At the same time, it is found that the magnetic moment per metal atom (Fe, Ni) decreases linearly with increasing carbon content for 0?x?0.25 with a slope of 1.2 μB/at. For high carbon content, x?0.5, it is observed that the decrease of lattice constant and increase of moment per metal atom (Fe, Ni) with increasing C content, indicates that the dissolution of carbon is hindered by the high-volume fraction of graphite in the initial powder mixture. The complete amorphization of x=0.5 does not occur after the extended ball milling. The alloying effect of carbon on the magnetization is compared with other metalloid B, P, and Si in Fe- and Ni-based binary system. 相似文献
219.
A new method has been found for the synthesis of pyrazoleacetate esters from pyrazolaldehyde. By a new tandem reaction, in which methyl 4‐pyrazoleacetate was reacted with carbon disulfide and iodomethane, thieno[2,3‐c]pyrazole was synthesized. This was an easy method for the synthesis of this type of heterocycle. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 303–305, 1999 相似文献
220.
The cyclization of 4-amino-5-(N-methyl-arylsulfonamido)methyl-1,2,4-triazole-3-thiones II , synthesized by the Reid and Heindel approach, with α-chloroacetophenone yields 7II-6-aryl-3-(N-methyl-arylsulfon-amido)methyl-s-triazolo[3,4-b][1,3,4]-thiazines III . Novel compounds II also react with benzyl chloride to afford 4-amino-3-benzylthio-5-(N-methyl-arylsulfonamido)methyl-1,2,4-triazole IV . © 1996 John Wiley & Sons, Inc. 相似文献