共查询到20条相似文献,搜索用时 15 毫秒
1.
Electrochemical synthesis of ordered CdTe nanowire arrays 总被引:1,自引:0,他引:1
A.W. Zhao G.W. Meng L.D. Zhang T. Gao S.H. Sun Y.T. Pang 《Applied Physics A: Materials Science & Processing》2003,76(4):537-539
Semiconductor CdTe nanowire arrays embedded in the nanochannels of the porous anodic alumina (PAA) template have been prepared
by using a potentiostatic electrochemical deposition method. The morphology and structure of the CdTe nanowire arrays have
been characterized by X-ray powder diffraction, transmission electron microscopy, and high-resolution transmission electron
microscopy. It is found that the CdTe nanowires with diameters and lengths of about 60 nm are single-crystalline with cubic
phase structure, uniformly and continuously embedded in the nanochannels of the PAA template. X-ray energy-dispersion analysis
and X-ray photoelectron spectroscopy analysis indicate that stoichiometric CdTe was formed. The growth mechanism of the CdTe
nanowires is also discussed.
Received: 11 June 2002 / Accepted: 2 July 2002 / Published online: 8 January 2003
RID="*"
ID="*"Corresponding author. Fax: +86-551/559-1434, E-mail: aiwuzhao@yahoo.com.cn 相似文献
2.
Highly oriented GaN nanowire arrays have been achieved by the catalytic reaction of gallium with ammonium. The resulting materials
were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (SEM), energy dispersive X-ray
spectroscopy (EDS), transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). SEM images show
that the resulting materials are nanowire arrays with a uniform length of about 10 μm. XRD, EDS, TEM and SAED indicate that
the nanowire arrays are single-crystal hexagonal GaN with a wurtzite structure. They have diameters of 10 to 20 nm.
Received: 2 October 2002 / Accepted: 7 October 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. E-mail: wwwangjc@sina.com 相似文献
3.
S.H. Sun G.W. Meng Y.W. Wang T. Gao M.G. Zhang Y.T. Tian X.S. Peng L.D. Zhang 《Applied Physics A: Materials Science & Processing》2003,76(2):287-289
Tin dioxide (SnO2) nanobelts have been successfully synthesized in bulk quantity by a simple and low-cost process based on the thermal evaporation
of tin powders at 800 °C. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations reveal
that the nanobelts are uniform, with lengths from several-hundred micrometers to a few millimeters, widths of 60 to 250 nm
and thicknesses of 10 to 30 nm. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX) and selected-area electron
diffraction analysis (SAED) indicate that the nanobelts are tetragonal rutile structure of SnO2. The SnO2 nanobelts grow via a vapor–solid (VS) process.
Received: 3 June 2002 / Accepted: 10 June 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +86-551/559-1434, E-mail: gwmeng@mail.issp.ac.cn 相似文献
4.
J.K. Jian X.L. Chen W.J. Wang L. Dai Y.P. Xu 《Applied Physics A: Materials Science & Processing》2003,76(2):291-294
Single-crystalline SnO2 nanowires, nanobelts and nanodendrites were synthesized by a simple gas-reaction route on a large scale at 900 °C. They were
characterized by means of X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive
X-ray spectroscopy (EDS), transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). FE-SEM images
showed that the products consisted of nanowires, nanobelts and nanodendrites that represent a novel morphology reported for
the first time. XRD, SAED and EDS indicated that they were single-crystalline tetragonal SnO2. The influence of experimental conditions on the morphologies of the products is discussed.
Received: 3 June 2002 / Accepted: 10 June 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: 86-10/82649531, E-mail: xlchen@aphy.iphy.ac.cn 相似文献
5.
Copper nanowire arrays for infrared polarizer 总被引:10,自引:0,他引:10
Y.T. Pang G.W. Meng Y. Zhang Q. Fang L.D. Zhang 《Applied Physics A: Materials Science & Processing》2003,76(4):533-536
A micropolarizer of copper nanowire arrays within anodic alumina membrane (AAM) was fabricated by anodization of pure Al foil
and electrodeposition of Cu, respectively. X-ray diffraction, scanning electron microscopy and transmission electron microscopy
investigations reveal that the ordered Cu nanowires are essentially single crystal, and have an average diameter of 90 nm.
Spectrophotometer measurements show that the copper nanowire arrays embedded in AAM can only transmit polarized light vertical
to the wires. An extinction ratio of 24 to 32 dB and an average insertion loss of 0.5 dB in the wavelength range of 1 to 2.2 μm
were obtained, respectively. Therefore Cu nanowire/AAM can be used as a wire grid type micropolarizer.
Received: 28 January 2002 / Accepted:17 May 2002 / Published online: 22 November 2002
RID="*"
ID="*"Corresponding author. Fax: +86-551/559-1434, E-mail: ytpang@263.net 相似文献
6.
Structural and optical properties of nanophase zinc oxide 总被引:7,自引:0,他引:7
Y. Du M.-S. Zhang J. Hong Y. Shen Q. Chen Z. Yin 《Applied Physics A: Materials Science & Processing》2003,76(2):171-176
Nanophase zinc oxide samples were synthesized by a two-step solid-state reaction method. The phase structure and microstructure
were investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The vibrational Raman spectra were
compared with those from the bulk and their grain size dependence was also examined. Their photoelectric behavior was studied
by X-ray photoelectron spectroscopy (XPS). The peaks at 1044.5 and 1021.4 eV were recorded as corresponding to the respective
binding energies of Zn 2p1/2 and Zn 2p3/2, and the photoelectron spectrum of O 1s in the as-prepared powder was located at 531.2 eV. A strong visible emission centered
at 580 nm was clearly observed in the nanosized zinc oxide at room temperature. Photoluminescence (PL) spectra were investigated
as a function of grain size after different heat treatments. The origin of the luminescence is attributed to the recombination
of electrons in singly occupied oxygen vacancies with photoexcited holes in the valence band.
Received: 30 June 2001 / Accepted: 20 February 2002 / Published online: 3 June 2002
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: mszhang@nju.edu.cn 相似文献
7.
The authors’ endeavors over the last few years with respect to boron nitride (BN) nanotube metal filling are reviewed. Mo
clusters of 1–2 nm in size and FeNi Invar alloy (Fe ∼60 at. %; Ni ∼40 at. %) or Co nanorods of 20–70 nm in diameter were embedded
into BN nanotube channels via a newly developed two-stage process, in which multi-walled C nanotubes served as templates for
the BN multi-walled nanotube synthesis. During cluster filling, low-surface-tension and melting-point Mo oxide first filled
a C nanotube through the open tube ends, followed by fragmentation of this filling into discrete clusters via O2 outflow and C→BN conversion within tubular shells at high temperature. During nanorod filling, C nanotubes containing FeNi
or Co nanoparticles at the tube tips were first synthesized by plasma-assisted chemical vapor deposition on FeNi Invar alloy
or Co substrates, respectively, and, then, the nanomaterial was heated to the melting points of the corresponding metals in
a flow of B2O3 and N2 gases. During this second stage, simultaneous filling of nanotubes with a FeNi or Co melt through capillarity and chemical
modification of C tubular shells to form BN nanotubes occurred. The synthesized nanocomposites were analyzed by scanning and
high-resolution transmission electron microscopy, electron diffraction, electron-energy-loss spectroscopy and energy-dispersive
X-ray spectroscopy. The nanostructures are presumed to function as ‘nanocables’ having conducting metallic cores (FeNi, Co,
Mo) and insulating nanotubular shields (BN) with the additional benefit of excellent environmental stability.
Received: 10 October 2002 / Accepted: 25 October 2002 / Published online: 10 March 2003
RID="*"
ID="*"Corresponding author. Fax: +81-298/51-6280, E-mail: golberg.dmitri@nims.go.jp 相似文献
8.
A.V. Karabutov V.D. Frolov E.N. Loubnin A.V. Simakin G.A. Shafeev 《Applied Physics A: Materials Science & Processing》2003,76(3):413-416
Low-threshold field electron emission (FEE) is reported for periodic arrays of micro-tips produced by laser ablation of Si
wafers. The best samples show emission at threshold fields as low as 4–5 V/μm for n-type Si substrates and of 1–2 V/μm for
p-doped Si substrates, as measured with a flat-screen technique. Auger electron spectroscopy and X-ray electron spectroscopy
reveal island-like deviation of the SiO2 stoichiometry on the tip surfaces, with lateral dimensions of less than 100 nm. Microscopic studies using a special field-emission
STM show that the emission originates from well-conducting regions of sub-micron size. The experimental data suggest FEE from
the tip arrays by a geometric field enhancement of both the individual micro-tip and the narrow conducting channels in the
tip body.
Received: 3 May 2002 / Accepted: 1 July 2002 / Published online: 28 October 2002
RID="*"
ID="*"Corresponding author. Fax: +7-095/135-82-34, E-mail: shafeev@kapella.gpi.ru 相似文献
9.
Manganese oxide (hausmannite) nanowires were prepared by annealing precursor powders at a temperature of 800 °C for 3 h, which
were produced in a novel inverse microemulsion (IμE) system. The microstructures of the as-prepared Mn3O4 nanowires were investigated by means of X-ray diffraction, transmission electron microscopy, and Raman spectra. It has been
found that the Mn3O4 nanowires were relatively straight and their surfaces were smooth with a typical diameter of 75–150 nm. The formation mechanism
of the Mn3O4 nanowires is discussed.
Received: 30 May 2002 / Accepted: 7 October 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: wangqun@nju.edu.cn 相似文献
10.
Changhyun Jin Kyungjoon Baek Sunghoon Park Hyoun Woo Kim Wan In Lee Chongmu Lee 《Solid State Communications》2010,150(37-38):1812-1817
CuO-core/ SnO2-shell one-dimensional nanostructures have been fabricated by thermal oxidation of a copper foil and then atomic layer deposition of SnO2. The structure and optical properties of the nanostructures have been investigated by using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, photoluminescence (PL) spectroscopy, and energy-dispersive X-ray analysis techniques. The nanostructures are found to have the form of nanorods, with the diameter of the CuO cores being in the range from a few tens to a few hundreds of nanometers, the thickness of the SnO2 shells being ~15 nm, and with a length of a few tens of micrometers. The CuO cores and the SnO2 shells of the as-synthesized nanorods have crystalline monoclinic CuO and amorphous SnO2 structures, respectively, but the SnO2 shells are found to crystallize to tetragonal SnO2 on thermal annealing. The PL emission intensity of the CuO nanorods has been slightly increased by SnO2 coating. The PL emission of the SnO2-coated CuO nanorods is somewhat increased and the emission peak position is red-shifted from 550 to 580 nm by annealing in a reducing atmosphere. On the other hand, the PL emission is significantly increased and the emission peak position is shifted from 550 nm further to around 595 nm by annealing in an oxidative atmosphere. In addition, the origins of the PL enhancements in the nanorods by coating and annealing are discussed. 相似文献
11.
V. Brien A. Dauscher P. Weisbecker F. Machizaud 《Applied Physics A: Materials Science & Processing》2003,76(2):187-195
The preparation in thin film form of the known icosahedral phase in Ti-Ni-Zr bulk alloys has been investigated as a function
of substrate temperature. Films were deposited by pulsed laser deposition on sapphire substrates at temperatures ranging from
room temperature to 350 °C. Morphological and structural modifications have been followed by grazing-incidence and θ–2θ X-ray
diffraction, transmission electron diffraction and imaging. Chemical composition has been analyzed by electron probe microanalysis.
The in-depth variation of composition has been studied by secondary neutral mass spectroscopy. We show that pulsed laser deposition
at 275 °C makes the formation of a 1-μm-thick film of Ti-Ni-Zr quasicrystalline textured nanocrystallites possible.
Received: 7 June 2001 / Accepted: 18 February 2002 / Published online: 3 June 2002
RID="*"
ID="*"Corresponding author. Fax: +33-3/8357-6300, E-mail: brien@mines.u-nancy.fr 相似文献
12.
ZnO–CuO core–shell nanorods and CuO-nanoparticle–ZnO-nanorod integrated structures were synthesized for the first time by
a two-stage solution process. Scanning electron microscopy and high-resolution transmission electron microscopy show that
the diameter and the length of the nanorods are around 60 and 800 nm, respectively. The morphologies of outer CuO could be
varied from nanoparticles to nanoshells by adjusting the solvent and dipping processes of copper (II) nitrate solution. The
CuO nanoparticles are single-crystalline or highly textured structures with size of around 30 nm. The CuO shell with thickness
of around 10 nm is constructed of nanocrystals with sizes in the range of 3–10 nm embedded in an amorphous matrix. Room-temperature
cathodoluminescence measurements of the CuO–ZnO nanocomposites exhibit relatively sharp ultraviolet emissions at 380 nm as
well as broad green and yellow emissions at 500 and 585 nm. The p-CuO/n-ZnO one-dimensional nanocomposites are promising for
optoelectronic nanodevice applications. 相似文献
13.
N.M. Huang C.S. Kan S. Radiman 《Applied Physics A: Materials Science & Processing》2003,76(4):555-559
An in situ technique for the synthesis of CdS nanoparticles in a ternary lyotropic cubic phase liquid crystal has been carried out.
The extremely viscous cubic phase liquid-crystal system consists of poly(oxyethylene)10 nonyl phenol ether as non-ionic surfactant, octane as oil phase and an aqueous phase containing reactant ions (Cd2+ and S2-). Thioacetamide (TAA) has been utilized as a source for slow release of sulfur in the in situ synthesis of CdS. Rheological results show that CdS nanoparticle growth did not disrupt the structure of the cubic phase
liquid-crystal system. This indicates that homogenous synthesis of CdS in the liquid crystal had been achieved. The final
products were characterized using X-ray photoelectron spectroscopy, thermal gravimetric analysis, transmission electron microscopy
and UV-visible spectroscopy. It was found that the CdS nanoparticles formed have a mesoporous structure with a size dependent
on the TAA decomposition aging time.
Received: 29 March 2002 / Accepted: 4 September 2002 / Published online: 17 December 2002
RID="*"
ID="*"Corresponding author. Fax: +603-8921/3257, E-mail: shahidan@pkrisc.cc.ukm.my 相似文献
14.
E. Majkova S. Luby R. Senderak Y. Chushkin M. Jergel I. Zergioti D. Papazoglou A. Manousaki C. Fotakis 《Applied Physics A: Materials Science & Processing》2003,76(5):763-766
The sub-picosecond laser microstructuring of multilayer gratings is presented in this paper. A micromachining system operating
with a 0.5 ps KrF laser at 248 nm was used to etch grating structures with a groove width of 1–2 μm in Mo/Si and Si/Mo multilayers.
Atomic force microscopy, scanning electron microscopy and X-ray reflectivity were used to characterize the microetched patterns.
The ω-scans around the 1st Bragg maximum show symmetric satellites up to 3rd order, with positions corresponding to the grating
period. The use of sub-picosecond laser pulses minimizes the thermally affected zone and enhances the quality of the etched
features. Short pulse laser processing is advantageous for the fabrication of high spatial resolution microstructures required
in X-ray optics.
Received: 21 May 2002 / Accepted: 19 August 2002 / Published online: 15 January 2003
RID="*"
ID="*"Corresponding author. Email: dpapa@iesl.forth.gr 相似文献
15.
G. Appel H. Ade A.G. Guerek S. Stadler R.P. Mikalo D. Schmeisser 《Applied Physics A: Materials Science & Processing》2003,76(2):177-182
Layers of dihydroxy silicon phthalocyanine tetrasulfonic acid and oligo-μ-oxo silicon phthalocyanine tetrasulfonic acid were
prepared by solution-casting methods. The purity of the material was checked by X-ray photoemission spectroscopy. The orientation
of the molecules in respect to the substrate plane was investigated by angle-dependent near-edge X-ray absorption fine-structure
spectroscopy. The morphology was characterized by atomic force microscopy. Most samples exhibited a significant orientation
that was accompanied by crystalline structures; others had no orientation at all with a dominant amorphous morphology. This
behavior indicates that several preparation parameters affect the crystallinity and the orientation of the phthalocyanines.
Received: 16 January 2002 / Accepted: 11 February 2002 / Published online: 3 May 2002
RID="*"
ID="*"Corresponding author. Fax: +1-919/515-7331, E-mail: harald_ade@ncsu.edu
RID="**"
ID="**"Present address: Southern Illinois University, Physics, Mailcode 4401, Carbondale, IL 62901, USA 相似文献
16.
Y. Liu D. Li R.Y. Zhu G.J. You S.X. Qian Y. Yang J.L. Shi 《Applied physics. B, Lasers and optics》2003,76(4):435-439
Au-core CdS-shell composite nanoparticles were synthesized by a direct self-assembly process and integrated into BaTiO3 thin films. Characterization by transmission electron microscopy showed that the average diameter of these composite nanoparticles
was about 8 nm. Using the femtosecond time-resolved optical Kerr effect method, we investigated the third-order nonlinear
optical response of the Au@CdS nanoparticles embedded in the BaTiO3 thin films at a wavelength of 800 nm. An ultrafast nonlinear response and a large effective third-order nonlinear susceptibility
of χ(3)=7.7×10-11 esu were observed. We attributed the enhancement of the third-order optical nonlinearity to a localized electric field effect
originating from the core-shell structure under off-surface-plasmon resonance conditions.
Received: 13 May 2002 / Revised version: 23 October 2002 / Published online: 3 April 2003
RID="*"
ID="*"Corresponding author. Fax: +86-21/6510-4949, E-mail: sxqian@fudan.ac.cn 相似文献
17.
C.L. Wang S.Z. Lin Y. Niu W.T. Wu Z.L. Zhao 《Applied Physics A: Materials Science & Processing》2003,76(2):157-163
A bulk nanocrystallined Ag50Ni alloy has been prepared by hot-pressing the mechanically pre-alloyed powders at 620 °C under
a normal pressure of 58 MPa in vacuum. The microstructural characteristics of the alloy were studied by X-ray diffraction
(XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results of the precise determination
of the lattice parameters of the phases in the powders and in the alloy by XRD show that, after mechanical alloying for 200 h,
the solid solubility of Ag in Ni reaches 4.85±0.21 at %, while that of Ni in Ag reaches 0.84±0.30 at %. After hot pressing,
the Ag- and Ni-rich phases in the alloy still show a certain degree of supersaturation, with a solid solubility of 0.45±0.11 at %
of Ag in Ni. After further annealing of the alloy at 700 °C for 24 h, the solubility decreases to a value of 0.21±0.11 at %
for Ag in Ni and to less than 0.1 at % for Ni in Ag. The grain size of the mechanically alloyed powders was of ca 6 nm. After
hot pressing, the grain size of the alloy increased to 40–60 nm and then grew further to 100–110 nm after annealing. The influence
of the variation of the grain size and the internal stress on the line breadth of the X-ray diffraction peaks has been evaluated
in detail. Finally, the role of the nanocrystalline structure in the fast densification process of the powders is also discussed.
Received: 12 September 2001 / Accepted: 18 Febraury 2002 / Published online: 10 September 2002
RID="*"
ID="*"Corresponding author. Fax: +86-24/2389-3624, E-mail: wwt@icpm.syb.ac.cn 相似文献
18.
Large-scale synthesis of rutile SnO2 nanorods 总被引:1,自引:0,他引:1
A high yield of tin oxide (SnO2) nanorods was obtained via annealing a nanoscale precursor in the molten salt flux and surfactant. X-ray diffraction, transmission electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction and infrared spectroscopy showed that the nanorods are composed of SnO2 with rutile structure. The surfactant and temperature have a profound influence on the production of SnO2 nanorods. 相似文献
19.
J.-M. Liu N. Chong H.L.W. Chan K.H. Wong C.L. Choy 《Applied Physics A: Materials Science & Processing》2003,76(1):93-96
Epitaxial (001) aluminum nitride (AlN) thin films on (111) Si substrates are prepared using pulsed-laser deposition. The epitaxial
structure of the as-prepared thin films is characterized by checking the X-ray-diffraction θ-2 θ scan and pole-figure, using
scanning electron microscopy, infrared radiation (IR) spectroscopy and Raman spectroscopy. The surface acoustic-wave resonance
at 345 MHz for a 1.5 μm thick AlN film on a (111) Si substrate is observed using an inter-digital electrode.
Received: 18 September 2001 / Accepted: 29 January 2002 / Published online: 3 June 2002
RID="*"
ID="*"Corresponding author. Fax: +86-25/359-5535, E-mail: liujm@nju.edu.cn 相似文献
20.
J.K. Jian X.L. Chen T. Xu Y.P. Xu L. Dai M. He 《Applied Physics A: Materials Science & Processing》2002,75(6):695-697
SnO2 nanowires were synthesized using a direct gas reaction route and were characterized by X-ray powder diffraction (XRD), scanning
electron microscopy (SEM), selected-area electron diffraction (SAED), high-resolution transmission electron microscopy (HRTEM)
and Raman-scattering spectroscopy. XRD, SEM, SAED and HRTEM indicated that the products were tetragonal SnO2 nanowires with diameters of 10–50 nm. The nanowires were single crystal and solid inside. Dendritic nanowires were observed
for the first time. Three vibrational modes were observed in the Raman spectra of the samples.
Received: 7 January 2002 / Accepted: 11 April 2002 / Published online: 19 July 2002 相似文献