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2002

Nanoscience and Nanotechnology

Articles 1 - 11 of 11

Full-Text Articles in Chemistry

Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin Nov 2002

Preparation And Electrochemical Lithium Intercalation Performance Of Different Shaped Carbon Nanotube, Mao-Hui Chen, Zhen-Cai Huang, Guo-Tao Wu, Jin-Kua You, Zu-Geng Lin

Journal of Electrochemistry

In the present work, different shaped carbon nanotubes were produced by the general CVD and the template method at different temperature (600 ℃,700 ℃) with the reaction gas of acetylene. The morphology, structure and the electrochemical lithium intercalation performance were comparatively studied and characterized by TEM, HRTEM, SEM, XRD, Raman techniques and Charge/Discharge Test. It was found that the different preparation methods and temperatures all had an obvious effect on these properties of carbon nanotubes. In our samples, with the increase of preparation temperature, the degree of crystallinity decreased, and the reversible specific capacity increased respectively.

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Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun Nov 2002

Nano-Sized Cobalt-Based Oxides As Negative Electrode For Lithium-Ion Batteries, Feng Huang, Zheng-Yong Yuan, Yun-Hong Zhou, Ju-Tang Sun

Journal of Electrochemistry

Nanosized cobalt-based oxide (Co 3O 4, CoB 1.36 O 2.8 and CoB 0.5 Al 0.1 O 1.5 ) samples were prepared by rheological phase method and were tested as anodes in secondary lithium batteries. The cells were cycled between 0.01V and 3.00 V. The best electrochemical performance was obtained from the Li/Co 3O 4 cell, which retained 95% of its initial capacity (931 mAh/g) after 30 cycles. The doping of B, Al reduced the reversible capacity during the first discharge/charge cycle, and the quantity of reversible capacity reduced with B, A1 increasing. The modifying structures at difference charge and discharge …

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Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin Nov 2002

Electrochemical Preparation And Reaction Mechanism Of Nanocrystalline Nio, Jia-Shan Gu, Ai-Jie Han, Xing-Fu Zhou, Dao-Bao Chu, Chang-Jian Lin

Journal of Electrochemistry

Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone mixed solutions and in the presence of Bu 4NBr (as an electron-conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR?HNMR?Raman spectra and the nano-powder was characterized by XRD and TEM. The results showed that the NiO powder after calcined at 450 ℃ had formed the cubic NaCl structure and the nanocrystalline NiO prepared by this method had narrow size distribution of 10～15 nm. Moreover, the product yield could be improved by controlling temperature below 30～40 ℃. The …

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Detection And Analysis Of Sec1 Immunological Reaction By Afm And Electrochemical Method, Sa-Ying Dong, Hong-Ren Wang Nov 2002

Detection And Analysis Of Sec1 Immunological Reaction By Afm And Electrochemical Method, Sa-Ying Dong, Hong-Ren Wang

Journal of Electrochemistry

The goals of this work were to demonstrate the ability of atomic force microscopy (AFM) to detect various immunological processes between antibodies and antigens.A sensor was designed by covalently linking the antibody of staphylococcal enterotoxin Cl (SEC1) on the self-assembled gold surface. This sensor permitted detection of antibody-antigen recognition events which were highly correlated with the topography under different conditions. The statistic data of AFM were analysed. As control experiments, nonspecific antigens and lower concentration SEC1 antigens were directly observed. In addition, an acidic solution was used to break the antigen-antibody pair and made the sensor reuse. Electrochemical evidence was …

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Pure Hap Film Prepared By Direct Electrodepositing On Metallic Surface And Its Mechanism, Hao-Bing Hu, Chang-Jian Lin, Fei Chen, Ren Hu, Ming Guo Aug 2002

Pure Hap Film Prepared By Direct Electrodepositing On Metallic Surface And Its Mechanism, Hao-Bing Hu, Chang-Jian Lin, Fei Chen, Ren Hu, Ming Guo

Journal of Electrochemistry

In controlling concentration of Ca 2+ and PO 4 3- in electrodeposition solution, the HAP film on Ti alloy has been deposited directly. Using XRD and SEM we have learned that prepared HAP is intact in crystal and equal in dimension. Thermodynamic calculation indicated that the HAP is easer formation of than that TCP of. With the XRD, SEM analyses and thermodynamic calculation, the electrodeposition mechanism has been discussed. It was proved that electrodepositon is a two_stage process and formation of HAP is a direct process from solution ions to HAP crystal without precursor.

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Facilitated K~+ Ion Transfer By Db18c6 Across The Micro Liquid/Liquid Interface, Dong-Ping Zhan, Bing-Liang Wu Aug 2002

Facilitated K~+ Ion Transfer By Db18c6 Across The Micro Liquid/Liquid Interface, Dong-Ping Zhan, Bing-Liang Wu

Journal of Electrochemistry

A novel microcavity Ag|AgCl electrode was fabricated to construct the micro_interface of two immiscible electrolyte solutions(ITIES). The transfer reactions of K + ion facilitated by DB18C6 across the water/1,2_DCE interface was investigated with the three_electrodes system. The corresponding reaction parameters were derived from the voltammetric data. The results showed that the microcavity electrode would be a useful and efficient tool to investigate the charge transfer reactions at ITIES.

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Syntheses And Photoluminescence Of Zinc Oxide Polyaniline Coaxial Nanowires And Their Array, Zhi-Xin Zheng, Yan-Yan Xi, Ping Dong, Huai-Guo Huang, Jian-Zhang Zhou, Lin-Lin Wu, Zhong-Hua Lin May 2002

Syntheses And Photoluminescence Of Zinc Oxide Polyaniline Coaxial Nanowires And Their Array, Zhi-Xin Zheng, Yan-Yan Xi, Ping Dong, Huai-Guo Huang, Jian-Zhang Zhou, Lin-Lin Wu, Zhong-Hua Lin

Journal of Electrochemistry

A novel nanomaterial,zinc oxide (ZnO) and polyaniline (PANI) coaxial nanowires and their array in the template,was synthesized using anodic aluminum oxide (AAO) membrane as template.The morphology of these coaxial nanowires was observed with transmission electron microscope (TEM).The experiments on photoluminescence (PL) of coaxial nanowires and their array in AAO membrane show that the visible emission band of ZnO shifts from 530 nm to 400 nm and the luminescence is enhanced for the coaxial nanowires array in AAO membrane,and the visible emission band shifts to a lower wavelergth(385 nm) for coatial nanowires in NaOH solution. Possible explanations for these two blue …

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The Preparation And Characterization Of Growing Preferentially Cds Nanopartile Film, Huai-Guo Huang, Yan-Yan Xi, Zhi-Xin Zheng, Jia-Wei Yan, Jian-Zhang Zhou, Ling-Ling Wu, Zhong-Hua Lin May 2002

The Preparation And Characterization Of Growing Preferentially Cds Nanopartile Film, Huai-Guo Huang, Yan-Yan Xi, Zhi-Xin Zheng, Jia-Wei Yan, Jian-Zhang Zhou, Ling-Ling Wu, Zhong-Hua Lin

Journal of Electrochemistry

CdS nanoparticle films were prepared on the PANI film,PATP film,Au film and ITO respectively by constant current deposition or current impulse method,and their structure and character were also studied.The results show that the substrates influence the structure and character of CdS particle film.

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Further Evidence For Surface Properties Of Porous Silicon Resulting In Electroluminescence, Zhan-Jun Zhang, Bin Wu, Jing-Jian Li, Zhong-Fan Liu, Sheng-Min Cai Feb 2002

Further Evidence For Surface Properties Of Porous Silicon Resulting In Electroluminescence, Zhan-Jun Zhang, Bin Wu, Jing-Jian Li, Zhong-Fan Liu, Sheng-Min Cai

Journal of Electrochemistry

The electroluminescence of porous silicon in solutions at positive biases was investigated by luminescence spectrometer. The electroluminescence of porous silicon in solutions mainly depended on its surface properties. The elelctroluminescence was much enhanced when the sample of porous silicon was electrolyzed once again which had undergone an electroluminescence test. The tests of both cyclic voltammetry and the luminescence of the sample of porous silicon prepared by repeated electrolysis provided further evidence that the electroluminescence of porous silicon in solutions at positive biases stemmed from the oxidation of Si_H on the surface of porous silicon. The voltage tunable emitting for porous …

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Raman Spectroscopic Study On Mechanism Of Aluminum Triphosphate Pigment, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su Feb 2002

Raman Spectroscopic Study On Mechanism Of Aluminum Triphosphate Pigment, Zhi-Jun Gu, Yong-Gui Liao, Zhi-Gang Zhang, Qi-Long Guo, Fang-Teng Su

Journal of Electrochemistry

The painted steel sample whose coating contained anticorrosive pigment has been investigated by Raman spectroscopy.The protective mechanism of aluminum triphosphate pigment for A3 steel is proposed as follows: Aluminum triphosphate can be dissolved and arrive at the surface of the steel.The dissolved triphosphate ions can complex with ferric ions.And the new products,namely ferric triphosphate,can strongly adhere at the surface of the steel by chemical bonds slowly.At last,a compact protective film,which effectively separates the steel substrate from the aggressive media,is formed at the steel surface.

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Photocurrent Enhancement By Ticl_4 Post_Treatment For Tio_2 Nanoporous Film Electrode, Yan-Jie Ren, Li Zhang, Sheng-Min Cai Feb 2002

Photocurrent Enhancement By Ticl_4 Post_Treatment For Tio_2 Nanoporous Film Electrode, Yan-Jie Ren, Li Zhang, Sheng-Min Cai

Journal of Electrochemistry

Enhanced photocurrent in dye_sensitized photoelectrochemical cell was obtained by post_treating the TiO 2 nanoporous film electrode with TiCl 4. By investigating the effect of the post_treatment on surface area, pore size distribution, laser pulse induced current transient of the film electrode, photocurrent increase by the post_treatment was assigned to the improved electron percolation resulting from broadening of interparticle neck.

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