以聚苯乙烯微球的单层和双层胶体晶体为模板,通过模板电沉积银,移除模板后得到单层和双层银通孔阵列,并用作基于增强光透射(EOT)的等离子传感器.结果表明,与单层银通孔阵列相比,双层通孔阵列的传感灵敏度和品质因子都有很大提升,最高分...以聚苯乙烯微球的单层和双层胶体晶体为模板,通过模板电沉积银,移除模板后得到单层和双层银通孔阵列,并用作基于增强光透射(EOT)的等离子传感器.结果表明,与单层银通孔阵列相比,双层通孔阵列的传感灵敏度和品质因子都有很大提升,最高分别达到559.71 nm/RIU(RIU:Refractive index unit)和14.28 RIU^(-1).展开更多
Deposition of diamond inside the trenches or microchannels by chemical vapor deposition （CVD） is limited by the diffusion efficiency of important radical species for diamond growth （H, CH3） and the pore depth of t...Deposition of diamond inside the trenches or microchannels by chemical vapor deposition （CVD） is limited by the diffusion efficiency of important radical species for diamond growth （H, CH3） and the pore depth of the substrate template. By ultrasonic seeding with nanodiamond suspension, three-dimensional （3D） penetration structure diamond was successfully deposited in cylindrical microchannels of Cu template by hot-filament chemical vapor deposition. Micro-Raman spectroscopy and scanning electron microscopy （SEM） were used to characterize diamond film and the effects of microchannel depth on the morphology, grain size and growth rate of diamond film were comprehensively investigated. The results show that diamond quality and growth rate sharply decrease with the increase of the depth of cylindrical microchannel. Individual diamond grain develops gradually from faceted crystals into micrometer cluster, and finally to ballas-type nanocrystalline one. In order to modify the rapid decrease of diamond quality and growth rate, a new hot filament apparatus with a forced gas flow through Cu microchannels was designed. Furthermore, the growth of diamond film by new apparatus was compared with that without a forced gas flow, and the enhancement mechanism was discussed.展开更多
We present a general approach to fabricate metal/TiO2 core/shell nanorod structures by twostep electrodeposition. Firstly, TiO2 nanotubes with uniform wall thickness are prepared in anodic aluminum oxide （AAO） membr...We present a general approach to fabricate metal/TiO2 core/shell nanorod structures by twostep electrodeposition. Firstly, TiO2 nanotubes with uniform wall thickness are prepared in anodic aluminum oxide （AAO） membranes by electrodeposition. The wall thickness of the nanotubes could be easily controlled by modulating the deposition time, and their outer diameter and length are only limited by the channel diameter and the thickness of the AAO membranes, respectively. The nanotubes＇ tops prepared by this method are open, while the bottoms are connected directly with the Au film at the back of the AAO membranes. Secondly, Pd, Cu, and Fe elements are filled into the TiO2 nanotubes to form core/shell structures. The core/shell nanorods prepared by this two-step process are high density and free-standing, and their length is dependent on the deposition time.展开更多
Copper indium diselenide nanorod arrays were electrodeposited on tungsten/silicon rigid substrates using porous anodic alumina as growth template. The porous anodic alumina templates were prepared by anodizing aluminu...Copper indium diselenide nanorod arrays were electrodeposited on tungsten/silicon rigid substrates using porous anodic alumina as growth template. The porous anodic alumina templates were prepared by anodizing aluminum films which were sputtered onto the tungsten/silicon substrates. A selective chemical etching was used to penetrate the barrier layer at the bottom of the alumina channels before electrodeposition, which enables direct electrical and chemical contact with the underside substrate electrode. The as-deposited samples were annealed at 450 ℃ in vacuum. Scanning electron microscopy revealed that the nanorods were dense and compact with diameter of about 100 nm, length of approximate 1 um, and the aspect ratio of 10. X-ray diffraction, micro-Raman spectroscopy, and high resolution transmission electron microscopy showed that chalcopyrite polycrystalline structure and high purity CuInSe2 nanorods were obtained. The grain size was large in the rod axial direction. Energy-dispersive X-ray spectroscopy showed the composition was nearly stoichiometric. The energy band gap of this nanorod arrays was analyzed by fundamental absorption spectrum and was evaluated to be 0.96 eV.展开更多
Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode...Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode surface. Effects of electrolytic parameters on the size of Ni particles were studied. The performances of hydrogen evolution and hydrogen storage of the Ni nanoparticles plating electrode were also investigated. The results indicate that the size of Ni nanoparticles decreases with the increase of Ni2+ concentration and the decrease of current density. The electrochemical activity of Ni nanoparticles plating electrode is much higher than that of bulk Ni electrode.展开更多
Well-aligned open-ended multi-walled carbon nanotube （MWCNT） arrays were prepared via chemical vapor deposition （CVD） method in porous anodic aluminum oxide （AAO） templates without depositing any transition meta...Well-aligned open-ended multi-walled carbon nanotube （MWCNT） arrays were prepared via chemical vapor deposition （CVD） method in porous anodic aluminum oxide （AAO） templates without depositing any transition metals as catalyst. Effects of the CVD temperature and heat treatment were studied in detail. Well-aligned open-ended MWCNT arrays were obtained at the CVD temperature above 600℃; when CVD temperature is reduced to around 550℃, CNTs, CNFs and other structures existed at the same time; no CNTs or carbon nanofibres （CNFs） could be fouad as the CVD temperature is below 500℃, and only amorphous carbon in the porous AAO template was found. Experimental results showed that the AAO template is catalytic during the CVD process, and it has the following two effects： to catalyze thermal decomposition of acetylene and to catalyze conversion of carbon decomposed from acetylene into CNTs or CNFs. Heat treatment could improve the graphitization degree, but it might also introduce new defects.展开更多
文摘以聚苯乙烯微球的单层和双层胶体晶体为模板,通过模板电沉积银,移除模板后得到单层和双层银通孔阵列,并用作基于增强光透射(EOT)的等离子传感器.结果表明,与单层银通孔阵列相比,双层通孔阵列的传感灵敏度和品质因子都有很大提升,最高分别达到559.71 nm/RIU(RIU:Refractive index unit)和14.28 RIU^(-1).
基金Project(21271188) supported by the Nature Science Foundation of China
文摘Deposition of diamond inside the trenches or microchannels by chemical vapor deposition （CVD） is limited by the diffusion efficiency of important radical species for diamond growth （H, CH3） and the pore depth of the substrate template. By ultrasonic seeding with nanodiamond suspension, three-dimensional （3D） penetration structure diamond was successfully deposited in cylindrical microchannels of Cu template by hot-filament chemical vapor deposition. Micro-Raman spectroscopy and scanning electron microscopy （SEM） were used to characterize diamond film and the effects of microchannel depth on the morphology, grain size and growth rate of diamond film were comprehensively investigated. The results show that diamond quality and growth rate sharply decrease with the increase of the depth of cylindrical microchannel. Individual diamond grain develops gradually from faceted crystals into micrometer cluster, and finally to ballas-type nanocrystalline one. In order to modify the rapid decrease of diamond quality and growth rate, a new hot filament apparatus with a forced gas flow through Cu microchannels was designed. Furthermore, the growth of diamond film by new apparatus was compared with that without a forced gas flow, and the enhancement mechanism was discussed.
基金This work is supported by the National Natural Science Foundation of China （No.10574122, No.50772110, No.50721091） and the National Basic Research Program of China （No.2011CB921400, No.2007CB925202, No.2009CB939901）.
文摘We present a general approach to fabricate metal/TiO2 core/shell nanorod structures by twostep electrodeposition. Firstly, TiO2 nanotubes with uniform wall thickness are prepared in anodic aluminum oxide （AAO） membranes by electrodeposition. The wall thickness of the nanotubes could be easily controlled by modulating the deposition time, and their outer diameter and length are only limited by the channel diameter and the thickness of the AAO membranes, respectively. The nanotubes＇ tops prepared by this method are open, while the bottoms are connected directly with the Au film at the back of the AAO membranes. Secondly, Pd, Cu, and Fe elements are filled into the TiO2 nanotubes to form core/shell structures. The core/shell nanorods prepared by this two-step process are high density and free-standing, and their length is dependent on the deposition time.
文摘Copper indium diselenide nanorod arrays were electrodeposited on tungsten/silicon rigid substrates using porous anodic alumina as growth template. The porous anodic alumina templates were prepared by anodizing aluminum films which were sputtered onto the tungsten/silicon substrates. A selective chemical etching was used to penetrate the barrier layer at the bottom of the alumina channels before electrodeposition, which enables direct electrical and chemical contact with the underside substrate electrode. The as-deposited samples were annealed at 450 ℃ in vacuum. Scanning electron microscopy revealed that the nanorods were dense and compact with diameter of about 100 nm, length of approximate 1 um, and the aspect ratio of 10. X-ray diffraction, micro-Raman spectroscopy, and high resolution transmission electron microscopy showed that chalcopyrite polycrystalline structure and high purity CuInSe2 nanorods were obtained. The grain size was large in the rod axial direction. Energy-dispersive X-ray spectroscopy showed the composition was nearly stoichiometric. The energy band gap of this nanorod arrays was analyzed by fundamental absorption spectrum and was evaluated to be 0.96 eV.
基金Projects(20673036,J0830415) supported by the National Natural Science Foundation of ChinaProject(09JJ3025) supported by Hunan Provincial Natural Science Foundation of ChinaProject(09GK3173) supported by the Planned Science and Technology Project of Hunan Province,China
文摘Ni nanoparticles plating was prepared in reverse microemulsion. The deposition was carried out through the Brownian motion of water pools in the reverse microemulsion and the adsorption of water pools on the electrode surface. Effects of electrolytic parameters on the size of Ni particles were studied. The performances of hydrogen evolution and hydrogen storage of the Ni nanoparticles plating electrode were also investigated. The results indicate that the size of Ni nanoparticles decreases with the increase of Ni2+ concentration and the decrease of current density. The electrochemical activity of Ni nanoparticles plating electrode is much higher than that of bulk Ni electrode.
基金This project was supported by the National High Technology Research and Development Program of China （863 Program, No. 2004AA302030） and Na- tional Natural Science Foundation of China （NSFC No. 60574095）. Tests and analysis are supported by the United Foundation for Testing ＆： Analysis in Hefei, Chi- nese Academy of Sciences.
文摘Well-aligned open-ended multi-walled carbon nanotube （MWCNT） arrays were prepared via chemical vapor deposition （CVD） method in porous anodic aluminum oxide （AAO） templates without depositing any transition metals as catalyst. Effects of the CVD temperature and heat treatment were studied in detail. Well-aligned open-ended MWCNT arrays were obtained at the CVD temperature above 600℃; when CVD temperature is reduced to around 550℃, CNTs, CNFs and other structures existed at the same time; no CNTs or carbon nanofibres （CNFs） could be fouad as the CVD temperature is below 500℃, and only amorphous carbon in the porous AAO template was found. Experimental results showed that the AAO template is catalytic during the CVD process, and it has the following two effects： to catalyze thermal decomposition of acetylene and to catalyze conversion of carbon decomposed from acetylene into CNTs or CNFs. Heat treatment could improve the graphitization degree, but it might also introduce new defects.
