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【资源】微纳米快报第一期 Vol 1, No 1 (2009)已有6人参与
上海交大创办英文国际学术期刊《纳米/微米快报》
高水平的科学研究需要一流的专业期刊和快速交流的载体。上海交通大学薄膜与微细加工技术教育部重点实验室与国际著名的OAHOST机构合作,面向纳米/微米尺度及多学科交叉的科研领域,于2009年第四季度创办了英文国际学术期刊《纳米/微米通讯》(Nano Micro Letters,NML,ISSN: 2150-5551)。张亚非教授担任期刊主编,加拿大科学院院士H. C. Liu教授和碳纳米管发现者、日本名城大学饭岛澄男教授为共同编辑,所有编委均为世界各地纳米/微米科研领域的顶尖科学家,张杰校长为该期刊题写了前言。
NML期刊采用国际最先进的OJS系统模式运作,期刊包含了纳米/微米研究领域权威性评论文章以及原创性科研论文,更有鲜明的网络时代特色:(1)读者可免费在线下载或浏览所有文章;(2)文章评审和出版过程快速高效;(3)所有文章经过相关领域权威专家的严格审稿;(4)刊登文章有大量主流网站转载、推介和检索。
纳米/微米快报 网址:http://nmletters.org/
快报第一期 Vol 1, No 1 (2009)
1. Multiple stacking of InGaAs/GaAs (731) nanostructures
Y. Z. Xie, V. P. Kunets, Z. M. Wang, V. Dorogan, Y. I. Mazur, J. Wu, G. J. Salamo
Abstract
We studied the multilayering effects of InGaAs quantum dots (QDs) on GaAs(731), a surface lying inside of the stereographic triangle. The surfaces after stacking 16 InGaAs layers were characterized with highly non-uniformity of QD spatial distribution. The bunched step regions driven by strain accumulation are decorated by QDs, therefore GaAs(731) becomes a good candidate substrate for the growth of QD clusters. The unique optical properties of the QD clusters are revealed by photoluminescence measurements. By adjusting the coverage of InGaAs, a bamboo-like nanostructured surface was observed and the quantum dots aligned up in clusters to separate the “bamboo” into sections.
Keywords: Quantum dots; MBE; High index surfaces; Nanostructures; Atomic force microscopy
http://www.nmletters.org/index.p ... w&path%5B%5D=24
2. One-dimensional GaN nanomaterials transformed from one-dimensional Ga2O3 and Ga nanomaterials
X. Y. Han, Y. H. Gao, X. H. Zhang
Abstract
One-dimensional (1D) GaN nanomaterials exhibiting various morphologies and atomic structures were prepared via ammoniation of either Ga2O3 nanoribbons, Ga2O3 nanorods or Ga nanowires filled into carbon nanotubes (CNTs). The 1D GaN nanomaterials transformed from Ga2O3 nanoribbons consisted of numerous GaN nanoplatelets having the close-packed plane, i.e. (0002)2H or (111)3C parallel to the axes of starting nanoribbons. The 1D GaN nanomaterials converted from Ga2O3 nanorods were polycrystalline rods covered with GaN nanoparticles along the axes. The 1D GaN nanomaterials prepared from Ga nanowires filled into CNTs displayed two dominant morphologies: (i) single crystalline GaN nanocolumns coated by CNTs, and (ii) pure single crystalline GaN nanowires. The cross-sectional shape of GaN nanowires were analyzed through the transmission electron microscopy (TEM) images. Formation mechanism of all-mentioned 1D GaN nanomaterials is then thoroughly discussed.
Keywords: GaN; One-dimensional; Ga2O3; Nanostructures
http://nmletters.org/index.php?j ... w&path%5B%5D=26
3. Semiconducting single-walled carbon nanotubes synthesized by S-doping
Z. J. Li, L. Wang, Y. J. Su, P. Liu, Y. F. Zhang
Abstract
An approach was presented for synthesis of semiconducting single-walled carbon nanotubes (SWNTs) by sulfur (S) doping with the method of graphite arc discharge. Raman spectroscopy, UV-vis-NIR absorption spectroscopy and electronic properties measurements indicated the semconducting properties of the SWNTs samples. Simulant calculation indicated that S doping could induce convertion of metallic SWNTs into semiconducting ones. This strategy may pave a way for the direct synthesis of pure semiconducting SWNTs.
Keywords: S-doping; Single-wall; Carbon nanotubes; Semiconducting; Arc discharge
http://nmletters.org/index.php?j ... w&path%5B%5D=27
4. Bilirubin adsorption property of mesoporous silica and amine-grafted mesoporous silica
L. X. Zhang, M. Zhu, L. M. Guo, L. Li, J. L. Shi
Abstract
Nephritic, hepatic and immune failures would lead to the overload of endogenous toxic molecules (e.g. bilirubin, cholic acid, uric acid, creatinine etc.) in human bodies. It is fatal in most cases and extracorporeal blood purification (ECBP) is powerful first-aid therapy. Adsorbents are key parts of ECBP apparatus. Mesoporous silicas should be promising candidates for these medical adsorbents, but there is no report about this. Herein, pure and amine-grafted mesoporous silicas have been applied to adsorb bilirubin, cholic acid, uric acid, creatinine and phenobarbital for the first time. These mesoporous materials show high adsorption capacities for bilirubin and uric acid in phosphate buffer solution (PBS). Effects of pore sizes, amine-modification, temperature and ionic strength on their bilirubin adsorption capacities have been studied in detail.
Keywords: Mesoporous silica; Bilirubin adsorption; Amine-grafted
http://nmletters.org/index.php?j ... w&path%5B%5D=28
5. Graded doped structure fabricated by vacuum spray method to improve the luminance of polymer light-emitting diodes
X. Mo, T. Mizokuro, C. Herk, N. Tanigaki, T. Hiraga
Abstract
An increase in luminance of a polymer light-emitting diode (PLED) was obtained by fabricating a graded doping structure using a vacuum spray method. The small electron transport molecule, Tris(8-hydroxyquinolinato)aluminum(III) (Alq3), was graded dispersed along the film in the direction of growth in the hole transport polymer poly(3-hexylthiophene-2,5-diyl) (P3HT, regiorandom) layer of the PLED, despite being dissolved in the same organic solvent as the polymer. The PLED reported here, which is composed of a graded structure, emitted brighter light than PLEDs composed of pure polymer or of a blend of active layers prepared by spin coating and/or vacuum spray methods.
Keywords: Polymer light-emitting diodes; Luminance; Graded doped; Vacuum spray
http://nmletters.org/index.php?j ... w&path%5B%5D=29
6. The Electrical Switching Characteristics of Single Copper Tetra-cyanoquinodimethane Nanowire
K. B. Zheng, H. T. Shen, C. N. Ye, J. L. Li, D. L. Sun, G. R. Chen
Abstract
In this paper, method combined vapor transportation with in-situ chemical reaction is employed to synthesize Cu(TCNQ) nanowires. The typical diameter of nanowires is 50-500 nm with high uniformity. The electrical switching characteristics of single nanowire are observed. The ON-OFF resistance ratio for switching reaches 104. The investigation reveals a linear relationship between the switching threshold and the spacing between the two electrodes. The temporal response of the switching process is 30 ns and the switch exhibits good reproducibility. The collapse of the nanowire under the condition of current surge is also discussed. It is believed that the Cu(TCNQ) nanowire could be promising for applications in nanoelectronics.
Keywords: Cu(TCNQ); Nanowire; Electrical switching; Charge transfer Complexes
http://nmletters.org/index.php?j ... w&path%5B%5D=30
7. A Vacuum Nano-casting Route to Magnetite Cores/Mesoporous Silica Shell Composites
L. M. Guo, J. L. Shi
Abstract
Hollow mesoporous silica spheres with magnetite cores (HMSMC) have been fabricated by Vacuum Nano-casting Route. The amount of magnetite cores and saturation magnetization value can be easily adjusted by changing the concentration of iron nitrate solution used in the synthesis procedure. Furthermore, the as-prepared HMSMCs still maintain narrow mesopore distribution, high surface area and large pore volume after the hollow cores of hollow mesoporous silica spheres were filled with magnetite particles. Specially, when the saturation magnetization value of as-prepared HMSMCs reaches 22.0 emu/g, the surface area and pore volume of corresponding HMSMCs are 149 m2/g and 0.19 cm3/g, respectively, and the pore size is 2.30 nm. The corresponding samples are characterized by X-ray diffraction, N2 sorption isotherms, transmission electron microscopy and vibrating-sample magnetometer.
Keywords: Hollow mesoporous silica spheres; Magnetite cores; Vacuum nano-casting
http://nmletters.org/index.php?j ... w&path%5B%5D=31
9. Schottky photodiode using submicron thick diamond epilayer for flame sensing
Y. Koide, M. Y. Liao, J. Alvarez, M. Imura, K. Sueishi, F. Yoshifusa
Abstract
The sensing of a flame can be performed by using wide-bandgap semiconductors, which offer a high signal-to-noise ratio since they only response the ultraviolet emission in the flame. Diamond is a robust semiconductor with a wide-bandgap of 5.5 eV, exhibiting an intrinsic solar-blindness for deep-ultraviolet (DUV) detection. In this work, by using a submicron thick boron-doped diamond epilayer grown on a type-Ib diamond substrate, a Schottky photodiode device structure- based flame sensor is demonstrated. The photodiode exhibits extremely low dark current in both forward and reverse modes due to the holes depletion in the epilayer. The photodiode has a photoconductivity gain larger than 100 and a threshold wavelength of 330 nm in the forward bias mode. CO and OH emission bands with wavelengths shorter than 330 nm in a flame light are detected at a forward voltage of -10 V. An alcohol lamp flame in the distance of 250 mm is directly detected without a focusing lens of flame light.
Keywords: Flame sensing; Boron-doped diamond; Schottky photodiode
http://nmletters.org/index.php?j ... w&path%5B%5D=32
10. Ballistic Current induced Effective Force on Magnetic Domain Wall
C. Wang, K. Xia
Abstract
The collective dynamics of magnetic domain wall under electric current is studied in the form of spin transfer torque (STT). The out-of-plane STT induced effective force is obtained based on the Landau-Lifshitz-Gilbert (LLG) equation including microscopic STT terms. The relation between microscopic calculations and collective description of the domain wall motion is established. With our numerical calculations based on tight binding free electron model, we find that the non adiabatic out-of-plane torque components have considerable non-local properties. It turns out that the calculated effective forces decay significantly with increasing domain wall widths.
Keywords: Magnetic Domain; Spin Transfer Torque; Spintronics; First Principle Study
http://nmletters.org/index.php?j ... w&path%5B%5D=33
11. Colloidal Silicon Nanocrystallites for Low-cost Solar Cell Development
V. ? vr??ek
Abstract
In this letter a formation of solution based of bulk-heterojunction based on freestanding silicon nanocrystals (Si-ncs) and conjugated ((poly(3-hexylthiophene) (P3HT) polymer is demonstrated. Surfactant free Si-ncs prepared by low-cost electrochemical etching are applied for fabrication of bulk-heterojunction and photo-conductive blends. We show that the optimum blend performance is at 40 wt.% nanocrystallites concentration within the P3HT polymer matrix. Furthermore, we illustrate that solar cell transport properties can be improved by nanosecond laser fragmentation of the nanocrystallites micrograins in ethanol. It argues that the Si-ncs/polymer blend with refine nanocrystaline structure may impact the development of low-cost solar cells by environmental- friendly mean.
Keywords: Silicon; Nanocrystals; Electrochemical etching; Solar cell
http://nmletters.org/index.php?j ... w&path%5B%5D=34
12Optical properties of ZnO and Mn-doped ZnO nanocrystals fabrication by vapor phase transport processes
Z. Wang, X. Y. Ma, J. W. Song, J. H. Yao
Abstract
In this paper we investigated the optical properties of ZnO and Mn doped ZnO nanocrystals that were fabricated by a vapor phase transport growth process, using zinc acetate dihydrate with or without Mn in a constant O2/Ar mixture gas flowing through the furnace at 400~600a??, respectively. The as grown ZnO nanocrystals are homogeneous with a mean size of 19 nm observed by scanning electron microscope (SEM). The optical characteristics were analyzed by absorption spectra and photoluminescence (PL) spectra at room-temperature. For ZnO nanocrystals, a strong and predominant UV emission peaked at 377 nm was found in the PL spectra. For Mn doped ZnO nanocrystals, in addition to the strong UV emission, a strong blue emission peaked at 435 nm was observed as well. By doping Mn ions, the major UV emission shifts from 377 nm to 408 nm, showing that Mn ions were not only incorporated into ZnO Ncs, but also introduced an impurity level in the bandgap. Moreover, with the concentration of Mn increasing, the relative intensities of the two emissions change largely, and the photoluminescence mechanism of them is discussed.
Keywords: ZnO and Mn-doped ZnO nanocrystals; Optical properties; Vapor phase transport growth
http://nmletters.org/index.php?j ... w&path%5B%5D=42
13.Synthesis of Ni nanowires via a hydrazine reduction route in aqueous ethanol solutions assisted by external magnetic fields
L. Y. Zhang, J. Wang, L. M. Wei, P. Liu, H. Wei, Y. F. Zhang
Abstract
One-dimensional Ni nanostructures were synthesized via a hydrazine reduction route under external magnetic fields. The mixture of de-ionized water and ethanol was used as the reaction solvent and hydrazine hydrate as reducing agents. The morphology and properties of Ni nanostructures were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). It was found that the magnetic field strength, concentration of Ni ions???reaction time and temperature as well as pH values played key roles on formation, microstructures and magnetic properties of Ni nanowires. The optimal wires have diameter of ~200 nm and length up to ~200 μm. And their coercivity is ~260 Oe, which is much larger than the commercial Ni powders of 31 Oe. This work presents a simple, low-cost, environment-friendly and large-scale production approach to fabricate one-dimensional magnetic materials. The resulting materials may have potential applications in conductive filters, magnetic sensors and catalytic agents.
Keywords: Ni fiber; Hydrazine reduction; Magnetic field; Magnetic properties
http://nmletters.org/index.php?j ... w&path%5B%5D=43 |
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