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
Shulin JI
,
Changhui YE
材料科学技术（英）
This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nanomaterials (mainly focusing on one-dimensional (1D) nanomaterials). In the first part of this article, we briefly introduce the importance, the synthesis methods and growth mechanisms, the properties and applications of ZnO 1D nanomaterials. In the second part of this article, the growth mechanisms of ZnO 1D nanomaterials will be discussed in detail in the framework of vapor-liquid-solid (VLS), vapor-solid (VS), and aqueous solution growth (ASG) approaches. Both qualitative and quantitative information will be provided to show how a controlled synthesis of ZnO 1D nanomaterials can be achieved. In the third part of this article, we present recent progresses in our group for the synthesis of ZnO 1D nanomaterials, and the results from other groups will only be mentioned briefly. Especially, experiment designing according to theories will be elaborated to demonstrate the concept of controlled synthesis. In the fourth part of this article, the properties and potential applications of ZnO 1D nanomaterials will be treated. Finally, a summary part will be presented in the fifth section. The future trend of research for ZnO 1D nanomaterials will be pointed out and key issues to be solved will be proposed.
关键词:
Zinc Oxide
,
Oxide
,
One-Dimensional
,
Nanomaterials
Xiaosheng FANG
材料科学技术（英）
In this review, the progress made during the last two years with respect to the syntheses and novel properties of one-dimensional (1D) ZnS nanostructures is presented. Primarily the research on 1D ZnS nanostructures has been of growing interest owing to their promising applications in nanoscale optoelectronic devices. Diverse 1D ZnS nanostructures with delicately-tuned morphologies, sizes, and microstructures have been synthesized through relatively simple and well-controlled techniques. Some novel properties of the nanomaterials have been explored and the relationships between their structural features and functions have been understood gradually.
关键词:
Semiconductors
,
ZnS
,
Nanomaterials
,
Nanostr
Haiwen Wang
材料科学技术（英）
Indium tin oxide (ITO) nanoparticles with crystallite size of 12.6 nm and specific surface area of 45.7 m2·g-1 were synthesized by co-precipitation method. The indium solution was obtained by dissolving metal indium in HNO3. The tin solution was obtained by dissolving metal tin in HNO3 and followed by stabilizing with citric acid. The free of chlorine ions in the synthesis process brought several advantages: shortening the synthesis time, decreasing the particle agglomeration, decreasing the chlorine content in the ITO nanoparticles and improving the particle sinterability. This is the first time to report the synthesis of ITO nanoparticles free from chlorine contamination without using the expensive metal alkoxides as starting materials.
关键词:
Nanomaterials
,
Powder technology
,
Indium tin oxide
,
Coprecipitation method
M. Maleki
材料科学技术（英）
One-dimensional CdS nanocrystals have been prepared by solvothermal method using cadmium acetate as a cadmium precursor, elemental sulfur and Na2S, as a sulfur precursor, and ethylenediamine as a solvent at 150°C for 5 h. The nanocrystals were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-Vis absorption spectroscopy. XRD patterns indicate that both Na2S and elemental sulfur as the sulfur precursor result in CdS nanorods with wurtzite phase (hexagonal structure). SEM and TEM images show that diameter of CdS nanorods can be decreased using Na2S instead of elemental sulfur. For the growth of CdS nanorods, a mechanism has been proposed. Uv-Vis absorption of CdS nanorods (sulfur precursor: Na2S) was shown blue shift to 485 nm due to the quantum size effect.
关键词:
Nanomaterials
W.L. Zhang
材料科学技术（英）
An axisymmetrical unit cell model was used to represent a bimodal Al alloy that was composed of both nano-grained (NG) and coarse-grained (CG) aluminum. Effects of microstructural and materials parameters on tensile properties of bimodal Al alloy were investigated by finite element method (FEM). The parameters analyzed included aspect ratios of CG Al and the unit cell, volume fraction of CG Al (VFCG), and yield strength and strain hardening exponent of CG Al. Aspect ratios of CG Al and the unit cell have no significant influence on tensile stress-strain response of the bimodal Al alloy. This phenomenon derives from the similarity in elastic modulus and coefficient of thermal expansion between CG Al and NG Al. Conversely, tensile properties of bimodal Al alloy are extremely sensitive to VFCG, yield strength and strain hardening exponent of CG Al. Specifically, as VFCG increases, both yield strength and ultimate tensile strength (UTS) of the bimodal Al alloy decreases, while uniform strain of bimodal Al alloy increases. In addition, an increase in yield strength of CG Al results in an increase in both yield stress and UTS of bimodal Al alloy and a decrease in uniform strain of bimodal Al alloy. The lower capability in lowering the increase of stress concentration in NG Al due to a higher yield strength of CG Al causes the lower uniform strain of the bimodal Al alloy. When strain hardening exponent of CG Al increases, 0.2% yield stress, UTS, and uniform strain of the bimodal Al alloy increases. This can be attributed to the increased work-hardening ability of CG Al with a higher strain hardening exponent.
关键词:
Nanomaterials
,
null
,
null
,
null
,
null
Haiqing Sun
材料科学技术（英）
Nanocrystalline Cu-Ni-P alloys with average grain sizes of 7, 10 and 24 nm were synthesized by means of electrodeposition. The grain size dependences of tensile strength and hardness of the nanocrystalline Cu alloys were investigated. The breakdown of Hall-Petch relation was exhibited in both tensile strength and hardness.
关键词:
Nanomaterials
Xiaosheng FANG
,
Lide ZHANG
,
null
材料科学技术（英）
This article reviews the recent developments in the controlled growth of one-dimensional (1D) oxide nanomaterials, including ZnO, SnO2, In2O3, Ga2O3, SiOx, MgO, and Al2O3. The growth of 1D oxide nanomaterials was carried out in a simple chemical vapor transport and condensation system. This article will begin with a survey of nanotechnology and 1D nanomaterials achieved by many researchers, and then mainly discuss on the controlled growth of 1D oxide nanomaterials with their morphologies, sizes, compositions, and microstructures controlled by altering experimental parameters, such as the temperature at the source material and the substrate, temperature gradient in the tube furnace, the total reaction time, the heating rate of the furnace, the gas flow rate, and the starting material. Their roles in the formation of various morphologies are analyzed and discussed. Finally, this review will be concluded with personal perspectives on the future research directions of this area.
关键词:
Controlled growth
,
null
,
null
,
null
Yongrui LI
,
Nanlin SHI
材料科学技术（英）
Ultrafine Fe3O4 powder was successfully synthesized via a novel ageing process from a precursor FeO(OH), which was the hydrolysate of FeCl3 in the urea solution. The structure of as-synthesized powder was characterized by X-ray diffraction (XRD), and the morphology of these nanoparticles was investigated using a transmission electron microscope (TEM). Pure phase Fe3O4 was obtained and the mean diameter of these nanoparticles was about 21nm. Furthermore, the study indicated that the precursor FeO(OH) played an important role in the formation of Fe3O4 nanoparticles. The mechanism was also discussed.
关键词:
Powder technology
,
null
,
null
,
null
Jian XIE
材料科学技术（英）
Li-storage intermetallic compound FeSb2 was prepared by solvothermal method and was studied as a promising anode material for secondary lithium-ion batteries. The as-prepared powder was characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The electrochemical Li-storage performances of this intermetallic anode were evaluated in a two-electrode cell Li/LiPF6(EC+DMC)/FeSb2. It was found that the particle size of FeSb2 powder is in nanoscale and this intermetallic anode exhibited enhanced cycling behavior comparing to its microscaled counterpart prepared by levitation-melting/ball-milling route.
关键词:
FeSb2
,
null
,
null
,
null
,
null
