Synthesis and Microstructures of α-Fe2O3 Bicrystalline Nanowires

2004 ◽  
Vol 839 ◽  
Author(s):  
R.M. Wang ◽  
Y.F. Chen ◽  
Y. Y. Fu ◽  
H. Zhang ◽  
C. Kisielowski
Keyword(s):  
Electron Microscopy ◽  
Growth Process ◽  
Oxidation Process ◽  
Solid Phase ◽  
X Ray Diffraction ◽  
Phase Growth ◽  
X Ray ◽  
Numerical Reconstruction ◽  
Transmission Electron ◽  
High Resolution Tem

ABSTRACTNovel Fe2O3 nanowires have been successfully synthesized by a simple oxidation process of pure iron. The microstructure of the Fe2O3 nanowires have been systematically investigated by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM). The investigated materials are found to be stoichiometric rhombohedral α-Fe2O3 with typical diameters of 20–80 nm and lengths up to 20 μm. In addition to known single crystal Fe2O3 nanowires, a great amount of novel bicrystalline nanowires were found with ellipsoidal heads. Investigations indicate that most of the bicrystalline nanowires are twins and their orientation relationship is obtained to be (−1, 1, 10)M//(−1, 1, 10)T, [110]M//[-1-10]T. High resolution TEM with numerical reconstruction of the electron exit wave was used to investigated the atomic structure of the micro-twins. Their growth mechanism is briefly discussed on the basis of solid phase growth process.

Structural and superconducting properties of melt-grown Y–Ba–Cu–O superconductors

1996 ◽  
Vol 11 (10) ◽  
pp. 2406-2415 ◽  
Author(s):  
R. Gopalan ◽  
T. Rajasekharan ◽  
T. Roy ◽  
G. Rangarajan ◽  
V. Ganesan ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Strain Field ◽  
Crack Width ◽  
Growth Process ◽  
Critical Radius ◽  
Radius Of Curvature ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

YBa2Cu3O7 (123) samples with varying Y2BaCuO5 (211) concentrations (0 mol%, 20 mol%, 28 mol%, and 50 mol%) were synthesized by the melt-growth process. Microstructural characterizations were done using x-ray diffraction (XRD), optical microscopy, scanning electron microscopy, and transmission electron microscopy (TEM). It was found that 123 platelet width, crack width between the platelets, and 211 particle size decreased systematically with increasing 211 concentration. TEM study showed that there is a critical radius of curvature (rc ≤ 0.2 μm-0.3 μm) of the 123/211 interface where defects/contrasts of strain field start to appear, and these defects are believed to be responsible for pinning the magnetic flux. Microhardness measurements showed that Vickers hardness (VHN) increases with increasing 211 content. Critical current density (Jc) values obtained from magnetization measurements using a SQUID magnetometer were found to increase in melt-grown samples by the addition of 211 content.

Growth and Characterization of Misostructural Zinc Oxide Tubes

2005 ◽  
Vol 23 ◽  
pp. 293-296
Author(s):  
X.W. Sun ◽  
C.X. Xu ◽  
B.J. Chen ◽  
Y. Yang
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Zinc Oxide ◽  
Growth Process ◽  
Hexagonal Structure ◽  
Metallic Zinc ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

Zinc oxide (ZnO) microtube has been fabricated by heating the mixture of ZnO and graphite powders in the atmosphere. The ZnO microtubes showed perfect hexagonal profiles with bell-mouth or normal hexagonal tops. Both X-ray diffraction (XRD) and high-resolution transmission electron microscopy (TEM) demonstrated that the product was composed of ZnO with typical hexagonal structure grown predominantly along (002) direction. The growth process was interpreted by means of vaporliquid-solid mechanism combining with the evaporation of metallic zinc.

Solvothermal Synthesis and Electrochemical Properties of Hairball-Like Bismuth Trisulphide Microcrystallines

2011 ◽  
Vol 233-235 ◽  
pp. 2289-2293
Author(s):  
Pin Jiang Li ◽  
Wen Jun Fa ◽  
Yan Ge Zhang ◽  
Bao Jun Huang ◽  
Yi Dong Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Solvothermal Synthesis ◽  
Growth Process ◽  
Solvothermal Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
One Step ◽  
Scanning Electron

Hairball-like bismuth trisulphide microcrystallines has been successfully prepared via one step solvothermal process and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) techniques. The morphologies of the Bi2S3 microcrystallines were influenced by reaction time, temperature, the mole ratio of the reactants and concentration of starting materials, and the growth process has been proposed. The electrochemical behavior of Bi2S3 was investigated using the cyclic voltammetry.

Nanorods of CoP, CdS, and ZnS

2006 ◽  
Vol 78 (9) ◽  
pp. 1651-1665 ◽  
Author(s):  
P. John Thomas ◽  
Paul Christian ◽  
Steven Daniels ◽  
Yang Li ◽  
Y. S. Wang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Structural Properties ◽  
Solution Phase ◽  
X Ray Diffraction ◽  
Phase Growth ◽  
Extrinsic Factors ◽  
X Ray ◽  
Transmission Electron

Simple thermolysis routes to CdS, ZnS, and CoP nanorods have been developed in our laboratory. The structural properties of the nanorods obtained were elucidated by means of X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HR-TEM). Arguments and calculations in support of the contention that intrinsic rather than extrinsic factors influence the solution-phase growth of nanorods are presented.

Initial formation mechanisms of (Ga1−xMnx)N nanorods grown on Al2O3 (0001) substrates

2008 ◽  
Vol 23 (12) ◽  
pp. 3275-3280 ◽  
Author(s):  
K.H. Lee ◽  
J.Y. Lee ◽  
H.C. Jeon ◽  
T.W. Kang ◽  
H.Y. Kwon ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Molecular Beam ◽  
Formation Mechanisms ◽  
X Ray Diffraction ◽  
Initial Formation ◽  
X Ray ◽  
Transmission Electron ◽  
High Resolution Tem ◽  
Xrd Patterns ◽  
Scanning Electron

The (Ga1−xMnx)N nanorods were grown on Al2O3 (0001) substrates by using rf-associated molecular beam epitaxy. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected-area diffraction pattern (SADP) results showed that the (Ga1−xMnx)N nanorods had (0001) preferential orientations. XRD patterns showed that the (Ga1−xMnx)N nanorods contained a small number of grains with different preferred orientations. High-resolution TEM (HRTEM) images showed that the (Ga1−xMnx)N nanorods consisted of different preferentially oriented grains. The initial formation mechanisms for the (Ga1−xMnx)N nanorods grown on Al2O3 (0001) substrates are described on the basis of the XRD, the TEM, the SADP, and the HRTEM results.

Transmission Electron Microscopy and X-Ray Diffraction Analysis of Aluminum-Induced Crystallization of Amorphous Silicon in α-Si:H/Al and Al/α-Si:H Structures

2005 ◽  
Vol 11 (2) ◽  
pp. 133-137 ◽  
Author(s):  
Ram Kishore ◽  
C. Hotz ◽  
H.A. Naseem ◽  
W.D. Brown
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Amorphous Silicon ◽  
Solid Phase ◽  
High Vacuum ◽  
Radiative Heating ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Xrd Studies

Solid phase crystallization of plasma-enhanced chemical-vapor-deposited (PECVD) amorphous silicon (α-Si:H) in α-Si:H/Al and Al/α-Si:H structures has been investigated using transmission electron microscopy (TEM) and X-ray diffraction (XRD). Radiative heating has been used to anneal films deposited on carbon-coated nickel (Ni) grids at temperatures between 200 and 400°C for TEM studies. α-Si:H films were deposited on c-Si substrates using high vacuum (HV) PECVD for the XRD studies. TEM studies show that crystallization of α-Si:H occurs at 200°C when Al film is deposited on top of the α-Si:H film. Similar behavior was observed in the XRD studies. In the case of α-Si:H deposited on top of Al films, the crystallization could not be observed at 400°C by TEM and even up to 500°C as seen by XRD.

THERMAL EVAPORATION SYNTHESIS OF ZnO MICROSHELLS

2005 ◽  
Vol 19 (15n17) ◽  
pp. 2722-2727
Author(s):  
Y. J. XING ◽  
D. P. YU ◽  
Z. H. XI ◽  
Z. Q. XUE
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Zinc Oxide ◽  
Growth Process ◽  
Thermal Evaporation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

We demonstrate the synthesis of zinc oxide microshells by thermal evaporation of ZnO and Zn powders. X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) observations reveal that the products are ZnO microshells with hollow cores, of which the wall thickness is about several hundred nanometers. The possible growth process is discussed.

ZnO/Graphene Composites: Synthesis, Characterization and Optical Properties

2014 ◽  
Vol 609-610 ◽  
pp. 76-81 ◽  
Author(s):  
Ling Wei Hu ◽  
Hua Tian ◽  
Yu Xia Zhang ◽  
Kun Lu ◽  
Ai Hua Jing
Keyword(s):  
Electron Microscopy ◽  
Aqueous Solution ◽  
Growth Process ◽  
Gas Sensing ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Potential Applications ◽  
Scanning Electron

ZnO/graphene composites has been synthesized using a one-pot hydrothermal method at moderate temperature of 90°C. Hydrothermal growth was done in an aqueous solution consisting of 20 mL graphene oxide (GO) solution (0.25 mg/mL) with equimolar of zinc acetate [ZAc, Zn (CH3COO)2·2H2 and hexamethylenetetramine (HMTA, C6H12N4). The as-synthesized composites was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectroscopy. The results of the characterization indicate that GO was reduced to graphene in the growth process, while ZnO in the form of quantum dots (QDs) or nanoparticles embedded in the graphene sheet. The composites synthesized by this method will have potential applications in bioimaging, gas sensing, optoelectrical materials and devices. The photoluminescence (PL) of the conposites was also investigated.

Synthesis and Microwave-Absorbing Properties of Ni-Carbon Sphere Composites

2011 ◽  
Vol 399-401 ◽  
pp. 552-555 ◽  
Author(s):  
Yuan Guang Zhang ◽  
Hong Yu Xia ◽  
Ying Guo Zhao
Keyword(s):  
Electron Microscopy ◽  
Solid Phase ◽  
Energy Dispersive Spectrometer ◽  
Synthetic Approach ◽  
Carbon Sphere ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microwave Absorbing Properties ◽  
Transmission Electron ◽  
Microwave Absorbing

A simple solid-phase synthetic approach has been exploited for the preparation of Ni-carbon sphere composites using Ni(CH3COO)2•4H2O as nickel source, and vitamin C (L-ascorbic acid) as reductant and carbon source at 500oC for 6 h. The products were characterized by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray energy dispersive spectrometer (EDS), raman spectroscopy and microwave-absorbing measurement. The results show that the products are composed of Ni-carbon sphere particles with average diameters of 1.2 µm. Each sphere particle contains embedded Ni particles with average diameters of 83 nm. The reflection loss (RL) values of the products are lower −10 dB at 2–18 GHz, displaying broad range of microwave absorption. Their minimum RL value is about −33 dB at 4.2 GHz, which exhibit good microwave absorbing properties.

V2O5 Nanorods with Improved Cycling Stability for Li Intercalation

2009 ◽  
Vol 1170 ◽  
Author(s):  
Alexey M Glushenkov ◽  
Vladimir I. Stukachev ◽  
Mohd Faiz Hassan ◽  
Gennady G. Kuvshinov ◽  
Hua Kun Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Energy Minimization ◽  
Scanning Transmission Electron Microscopy ◽  
Growth Process ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Spin Resonance ◽  
Scanning Transmission ◽  
Oxidation Surface

AbstractWe have recently reported a solid-state, mass-quantity transformation from V2O5 powders to nanorods via a two-step approach [1]. In this paper we present detailed investigation of the growth process using x-ray diffraction, scanning/transmission electron microscopy and electron spin resonance. The growth of nanorods at intermediate stages has been examined. Oxidation, surface energy minimization and surface diffusion play important roles in the growth mechanism.

Sign in / Sign up

Export Citation Format

Share Document