Guozhen SHEN
,
Di CHEN
材料科学技术（英）
One-dimensional (1-D) nanostructures have been attracted much attention as a result of their exceptional properties, which are different from bulk materials. Among 1-D nanostructures, 1-D heterostructures with modulated compositions and interfaces have recently become of particular interest with respect to potential applications in nanoscale building blocks of future optoelectronic devices and systems. Many kinds of methods have been developed for the synthesis of 1-D nanoscale heterostructures. This article reviews the most recent development, with an emphasize on our own recent efforts, on 1-D nanoscale heterostructures, especially those synthesized from the vapor deposition methods, in which all the reactive precursors are mixed together in the reaction chamber. Three types of 1-D nanoscale heterostructures, defined from their morphologies characteristics, are discussed in detail, which include 1-D co-axial core-shell heterostructures, 1-D segmented heterostructures and hierarchical heterostructures. This article begins with a brief survey of various methods that have been developed for synthesizing 1-D nanoscale heterostructures and then mainly focuses on the synthesis, structures and properties of the above three types of nanoscale heterostructures. Finally, this review concludes with personal views towards the topic of 1-D nanoscale heterostructures.
关键词:
Nanostructures
,
Heterostructures
,
One-dime
Xifeng Lu
材料科学技术（英）
Porous indium oxide nanorods have been synthesized by calcination of indium hydroxide, which were prepared through a simple sol-gel and aging process at low temperature in the presence of sodium dodecyl sulfate (SDS). X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) were adopted to characterize the phase composition and morphology of the resulted samples. The sensing properties towards H2 were examined at 340°C, which showed better sensitivity and quick response/recovery merits.
关键词:
Nanostructures
K.M.K. Srivatsa
材料科学技术（英）
Anatase titania nanostructures have been synthesized at room temperature by plasma enhanced chemical vapor deposition (PECVD) process on silicon (100) substrates using titanium tetraisopropoxide [Ti(OC3H7)4, TTIP] vapor, argon and oxygen mixtures under various deposition pressures. The deposited titania has been characterized for its structural, morphological and chemical composition by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray (EDX) spectroscopy and Fourier transform infrared (FTIR) spectroscopy recordings. With the variation of deposition pressure, titania assumes various nanostructures viz. nanocrystals, nanoparticles, noanorods and comb-like structure. EDX and FTIR measurements show that the deposited titania is of high chemical purity. The possible growth mechanisms for the observed titania nanostructures have been discussed.
关键词:
Nanostructures
Xifeng Lu
材料科学技术（英）
Poly-crystalline In(OH)3 nanorods have been successfully prepared via a urea-based precipitation using the colloidal carbon spheres as the templates. After calcinations, the resulted In2O3 nanorods with poly-crystalline structure were fabricated. Structure and morphology of the product were characterized by X-ray diffraction (XRD), and transmission electron microscopy (TEM). The possible formation process was schemed. The sensor gas properties towards C2H5OH and CO were examined.
关键词:
Nanostructures
Mu Zhao
材料科学技术（英）
The catalytic graphitization of thermal plastic phenolic-formaldehyde resin with the aid of ferric nitrate (FN) was studied in detail. The morphologies and structural features of the products including onion-like carbon nanoparticles and bamboo-shaped carbon nanotubes were investigated by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction and Raman spectroscopy measurements. It was found that with the changes of loading content of FN and residence time at 1000°C, the products exhibited various morphologies. The TEM images showed that bamboo-shaped carbon nan-otube consisted of tens of bamboo sticks and onion-like carbon nanoparticle was made up of quasi-spherically
concentrically closed carbon nanocages.
关键词:
Nanostructures
T.Rol
,
M.Ya
,
D.Retraint
,
K.Lu
,
J.Lu
材料科学技术（英）
Surface mechanical attrition treatment (SMAT) can produce a nanometer-grained surface layer without porosity and contamination on a bulk stainless steel. The nanostructured layer has high strength that contributes to an overall increase in the mechanical properties of the nanostructured sample. In this study, a new nanostructured composite was developed by assembling three SMA-treated thin plates. An FEM model based on nanoindentation data was established to simulate the stress-strain relationship. The simulation and the experimental tension curve correspond well. Moiré interferometry was used to observe the tensile behavior of the new composite in real time. A tension test conducted on a specimen consisting of three 500~μm thick SMA-treated sheets showed that the yield stress is much higher than that of a bulk-treated sample of the same total thickness. Based on these results, the new multilayer composite would seem to be a promising structural material due to its high strength/weight ratio.
关键词:
Nanostructures
,
null
,
null
,
null
Mu Zhao
材料科学技术（英）
The catalytic graphitization of thermal plastic phenolic-formaldehyde resin with the aid of ferric nitrate (FN) was studied in detail. The morphologies and structural features of the products including onion-like carbon nanoparticles and bamboo-shaped carbon nanotubes were investigated by transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray diffraction and Raman spectroscopy measurements. It was found that with the changes of loading content of FN and residence time at 1000°C, the products exhibited various morphologies. The TEM images showed that bamboo-shaped carbon nan-otube consisted of tens of bamboo sticks and onion-like carbon nanoparticle was made up of quasi-spherically
concentrically closed carbon nanocages.
关键词:
Nanostructures
Xifeng Lu
材料科学技术（英）
Porous indium oxide nanorods have been synthesized by calcination of indium hydroxide, which were prepared through a simple sol-gel and aging process at low temperature in the presence of sodium dodecyl sulfate (SDS). X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) were adopted to characterize the phase composition and morphology of the resulted samples. The sensing properties towards H2 were examined at 340°C, which showed better sensitivity and quick response/recovery merits.
关键词:
Nanostructures
Xiaosheng FANG
材料科学技术（英）
One-dimensional (1D) nanomaterials and nanostructures have received much attention due to their potential interest for understanding fundamental physical concepts and for applications in constructing nanoscale electric and optoelectronic devices. Zinc sulfide (ZnS) is an important semiconductor compound of II-VI group, and the synthesis of 1D ZnS nanomaterials and nanostructures has been of growing interest owing to their promising application in nanoscale optoelectronic devices. This paper reviews the recent progress on 1D ZnS nanomaterials and nanostructures, including nanowires, nanowire arrays, nanorods, nanobelts or nanoribbons, nanocables, and hierarchical nanostructures etc. This article begins with a survey of various methods that have been developed for generating 1D nanomaterials and nanostructures, and then mainly focuses on structures, synthesis, characterization, formation mechanisms and optical property tuning, and luminescence mechanisms of 1D ZnS nanomaterials and nanostructures. Finally, this review concludes with personal views towards future research on 1D ZnS nanomaterials and nanostructures.
关键词:
One-dimensional
,
ZnS
,
Nanomaterials
,
Nanost
