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991.
Facile electrochemical synthesis of hexagonal Cu2O nanotube arrays and their application 总被引:1,自引:0,他引:1
Large-scale and highly oriented single-crystalline hexagonal Cu(2)O nanotube arrays have been successfully synthesized using a two-step solution approach, which involves the electrodeposition of oriented Cu(2)O nanorods and a subsequent dissolution technique along the c axis to form a tubular structure. Herein, NH(4)Cl was found to be an effectual additive, and it can successfully realize the dissolution process of Cu(2)O from nanorods to nanotubes. The dissolution mechanism of Cu(2)O from nanorods to nanotubes was illustrated in detail. These prepared Cu(2)O nanotube arrays were characterized by SEM, EDS, XRD, XPS, and TEM. The photoluminescence (PL) spectrum of Cu(2)O nanotube arrays was also measured, and it shows there is a greater fraction of copper or oxygen vacancies in these prepared Cu(2)O nanotubes. Finally, the applications of Cu(2)O nanotube arrays for gas sensors were investigated in this paper. 相似文献
992.
Using the multireference configuration interaction method with a Davidson correction and a large orbital basis set (aug-cc-pVQZ), we obtain an energy grid that includes 32 038 points for the construction of a new analytical potential energy surface (APES) for the Ne + H(2)(+) → NeH(+) + H reaction. The APES is represented as a many-body expansion containing 142 parameters, which are fitted from 31?000 ab initio energies using an adaptive nonlinear least-squares algorithm. The geometric characteristics of the reported APES and the one presented here are also compared. On the basis of the APES we obtained, reaction cross sections are computed by means of quasi-classical trajectory (QCT) calculations and compared with the experimental and theoretical data in the literature. 相似文献
993.
The effect of the Si-H bond on the gas-phase reaction chemistry of trimethylsilane in the hot-wire chemical vapor deposition (HWCVD) process has been studied by examining its decomposition on a hot tungsten filament and the secondary gas-phase reactions in a reactor using a soft laser ionization source coupled with mass spectrometry. Trimethylsilane decomposes on the hot filament via Si-H and Si-CH(3) bond cleavages. A short-chain mechanism is found to dominate in the secondary reactions in the reactor. It has been shown that the hydrogen abstractions of both Si-H and C-H occur simultaneously, with the abstraction of Si-H being favored. Tetramethylsilane and hexamethyldisilane are the two major products formed from the radical recombination reactions in the termination steps. Three methyl-substituted disilacyclobutane molecules, i.e., 1,3-dimethyl-1,3-disilacyclobutane, 1,1,3-trimethyl-1,3-disilacyclobutane, and 1,1,3,3-tetramethyl-1,3-disilacyclobutane are also produced in reactor from the cycloaddition reactions of methyl-substituted silene species. Compared to tetramethylsilane and hexamethyldisilane, a common feature with trimethylsilane is that the short-chain mechanism still dominates. However, a more active involvement of the reactive silene intermediates has been found with trimethylsilane. 相似文献
994.
Qiu F Tu C Wang R Zhu L Chen Y Tong G Zhu B He L Yan D Zhu X 《Chemical communications (Cambridge, England)》2011,47(34):9678-9680
By using a cosolvent self-assembly approach, the emission of multi-micelle aggregates from star copolymer unimolecular micelles is enhanced greatly through restriction of concentration self-quenching and intermolecular aggregation of a conjugated polymer core, due to the existence of a PEG shell of HCP-star-PEG unimolecular micelles. 相似文献
995.
FETs based on Au-impregnated polyacrylonitrile (PAN)/polythiophene (PTH) core-shell nanofibers have been fabricated and exhibit high mobility (~2.0 cm(2) V(-1) s(-1)). 相似文献
996.
TiO(2) nanocrystals are assembled together by interfacial Ti-Ti electronic bonding. Such nanocrystal assemblies have a narrower band gap, greatly enhanced visible light absorption, and solar photocatalysis compared with individual nanocrystals. 相似文献
997.
Zhang X Lu X Shen Y Han J Yuan L Gong L Xu Z Bai X Wei M Tong Y Gao Y Chen J Zhou J Wang ZL 《Chemical communications (Cambridge, England)》2011,47(20):5804-5806
Three-dimensional (3D) WO(3) nanostructures were grown on carbon paper by a catalyst-free high temperature reactive vapor deposition process, which exhibit a good photoelectrochemical property and visible light driven photocatalytic performance. 相似文献
998.
Chen-Zhong Yao Hui-Xuan Ma Xi-Sheng Zhang Li-Xin Meng Li-Ping Zhao Ling Tai Yu-Chun Wang Qiao-Juan Gong Ye-Xiang Tong 《Journal of Solid State Electrochemistry》2011,15(6):1193-1199
Magnetic dendrites of Co
x
Pb1−x
were fabricated through potentiostatic electrochemical deposition on Cu substrates in boric acid solution at room temperature.
The as-deposited dendrites were determined by scanning electron microscopy (SEM), X-ray diffraction (XRD), transmission electron
microscopy (TEM), electrodeposition (ED), and energy dispersive X-ray spectroscopy (EDS). SEM results indicate that the Co
x
Pb1−x
dendrites are highly symmetrical in structures. The diameters of the branches are about 50 ~ 200 nm, and the backbones are
continuous with lengths up to about 10 μm. XRD patterns show that the as-deposited dendrites are solid solutions. The annealing
treatment can result in the recrystallization of these metastable alloys into two separate phases. TEM, ED, and EDS results
also reveal that the backbones and the branches of the dendrites are composed of different amounts of cobalt. Magnetic measurements
confirm that the as-deposited Co
x
Pb1−x
dendrites have a softly ferromagnetic behavior, and a small coercive force (about 80 Oe). Also the saturation magnetizations
of the Co
x
Pb1−x
dendrites decrease rapidly with the temperature increasing. 相似文献
999.
1000.