Two-step oxygen injection process for growing ZnO nanorods

Uniform hexagonal prismatic zinc oxide rods were grown over the entire alumina substrate at 550°C using a two-step oxygen injection process, whether the substrates were coated with a catalyst or not. X-ray diffraction showed that all of the depositions exhibited a preferred orientation in the (002) plane. The influence of oxygen concentration was investigated by changing the oxygen flow rate. Oxygen concentration affected the size of ZnO nanorods, especially the diameter. The ZnO nanorods were further checked using high-resolution transmission electron microscopy, photoluminescence, Raman spectroscopy, and room-temperature ultraviolet lasing. The results showed that the rods were single crystals and had excellent optical properties. By observing the growth process, we found that the diameter increased slowly, but the longitudinal growth rate was very high. The growth of ZnO nanorods revealed that the uniform hexagonal prismatic ZnO nanorods were synthesized through vapor deposition growth and a self-catalyzed vapor–liquid–solid (VLS) process.

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Photoluminescence Enhancement of CdS Nanocrystals Fabricated on Dithiocarbamate Functionalized PET Substrates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1511 ◽

2012 ◽

Vol 512-515 ◽

pp. 1511-1515

Author(s):

Chun Lin Zhao ◽

Li Xing ◽

Xiao Hong Liang ◽

Jun Hui Xiang ◽

Fu Shi Zhang ◽

...

Keyword(s):

Room Temperature ◽

Hexagonal Structure ◽

Diffraction Measurement ◽

X Ray Diffraction ◽

Visible Absorption ◽

X Ray ◽

Cds Nanocrystals ◽

Morphological Studies ◽

Transmission Electron

Cadmium sulfide (CdS) nanocrystals (NCs) were self-assembled and in-situ immobilized on the dithiocarbamate (DTCs)-functionalized polyethylene glycol terephthalate (PET) substrates between the organic (carbon disulfide diffused in n-hexane) –aqueous (ethylenediamine and Cd2+ dissolved in water) interface at room temperature. Powder X-ray diffraction measurement revealed the hexagonal structure of CdS nanocrystals. Morphological studies performed by scanning electron microscopy (SEM) and high-resolution transmission electron microscope (HRTEM) showed the island-like structure of CdS nanocrystals on PET substrates, as well as energy-dispersive X-ray spectroscopy (EDS) confirmed the stoichiometries of CdS nanocrystals. The optical properties of DTCs modified CdS nanocrystals were thoroughly investigated by ultraviolet-visible absorption spectroscopy (UV-vis) and fluorescence spectroscopy. The as-prepared DTCs present intrinsic hydrophobicity and strong affinity for CdS nanocrystals.

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Facile Organometallic Synthesis of Fe-Based Nanomaterials by Hot Injection Reaction

Nanomaterials ◽

10.3390/nano11051141 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1141

Author(s):

Georgia Basina ◽

Hafsa Khurshid ◽

Nikolaos Tzitzios ◽

George Hadjipanayis ◽

Vasileios Tzitzios

Keyword(s):

Room Temperature ◽

Colloidal Particles ◽

Iron Pentacarbonyl ◽

Vibrating Sample Magnetometer ◽

X Ray Diffraction ◽

Organometallic Synthesis ◽

X Ray ◽

Transmission Electron ◽

Hot Injection ◽

The Stability

Fe-based colloids with a core/shell structure consisting of metallic iron and iron oxide were synthesized by a facile hot injection reaction of iron pentacarbonyl in a multi-surfactant mixture. The size of the colloidal particles was affected by the reaction temperature and the results demonstrated that their stability against complete oxidation related to their size. The crystal structure and the morphology were identified by powder X-ray diffraction and transmission electron microscopy, while the magnetic properties were studied at room temperature with a vibrating sample magnetometer. The injection temperature plays a very crucial role and higher temperatures enhance the stability and the resistance against oxidation. For the case of injection at 315 °C, the nanoparticles had around a 10 nm mean diameter and revealed 132 emu/g. Remarkably, a stable dispersion was created due to the colloids’ surface functionalization in a nonpolar solvent.

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ION CHANNELING AND PIXE STUDIES OF S IMPLANTATION IN GaAs

International Journal of PIXE ◽

10.1142/s0129083592000142 ◽

1992 ◽

Vol 02 (02) ◽

pp. 151-159

Author(s):

LIU SHIJIE ◽

WANG JIANG ◽

HU ZAOHUEI ◽

XIA ZHONGHUONG ◽

GAO ZHIGIANG ◽

...

Keyword(s):

Room Temperature ◽

Dislocation Loops ◽

Good Recovery ◽

Electrical Measurements ◽

X Ray ◽

Defect Complexes ◽

Ion Channeling ◽

Transmission Electron ◽

Activation Efficiency ◽

Very High

GaAs (100) crystals were implanted with 100 keV S+ to a dose of 3×1015 cm−2 in a nonchanneling direction at room temperature, and treated with rapid thermal annealing (RTA). He+ Rutherford backscattering and particle-induced X-ray emission in channeling mode in combination with transmission electron microscopy (TEM) were used to study the damage and the lattice location of S atoms. It is revealed that the RTA at 950 °C for 10 sec has resulted in a very good recovery of crystallinity with a few residual defects in the form of dislocation loops, and a very high substitutionality (~90%). The activation efficiency and the Hall mobility of the implanted samples are found to be low after the electrical measurements. Based on these results an extended dopant diffusion effect for the residual defects and a correlation between the electrical properties and defect complexes are suggested.

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Synthesis and Photoluminescence Properties of Novel SnO2 Zigzag Nanoribbons

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.4213 ◽

2010 ◽

Vol 97-101 ◽

pp. 4213-4216

Author(s):

Jian Xiong Liu ◽

Zheng Yu Wu ◽

Guo Wen Meng ◽

Zhao Lin Zhan

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Vapour Deposition ◽

Chemical Vapour ◽

Photoluminescence Properties ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Ceramic Boat

Novel single-crystalline SnO2 zigzag nanoribbons have been successfully synthesized by chemical vapour deposition. Sn powder in a ceramic boat covered with Si plates was heated at 1100°C in a flowing argon atmosphere to get deposits on a Si wafers. The main part of deposits is SnO2 zigzag nanoribbons. They were characterized by means of X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and selected-area electron diffraction (SAED). SEM observations reveal that the SnO2 zigzag nanoribbons are almost uniform, with lengths near to several hundred micrometers and have a good periodically tuned microstructure as the same zigzag angle and growth directions. Possible growth mechanism of these zigzag nanoribbons was discussed. A room temperature PL spectrum of the zigzag nanoribbons shows three peaks at 373nm, 421nm and 477nm.The novel zigzag microstructures will provide a new candidate for potential application.

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Preparation and Properties of Nano-Crystalline Cellulose Electro-Rheological Fluid

Materials Science Forum ◽

10.4028/www.scientific.net/msf.815.217 ◽

2015 ◽

Vol 815 ◽

pp. 217-221

Author(s):

Ling Li Xu ◽

Xing Ling Shi ◽

Qing Liang Wang

Keyword(s):

Room Temperature ◽

Silicone Oil ◽

Strong Acid ◽

Crystalline Cellulose ◽

Methyl Silicone ◽

Shearing Stress ◽

X Ray Diffraction ◽

X Ray ◽

Nano Crystalline ◽

Transmission Electron

nanocrystalline cellulose (NCC) was prepared from micro-crystalline cellulose (MCC) by strong acid hydrolysis. The characteristics of such particle were studied by transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. Electro-rheological fluids (ERF) were prepared by dispersing NCC and MCC in methyl-silicone oil, and their ER effects were measured. Experimental results indicated that NCC ERF exhibited a remarkable ER effect. The highest static shearing stress of NCC ERF (3.5 g/ml) was 5.1 kPa at the room temperature under a 4 .2 kV/mm electric field, increased about 5.5 times compared to MCC ERF, and sedimentation of NCC ERF was not observed even after 60 days.

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Phase Transformation of Powdered Material by Using Metal Jet

Materials Science Forum ◽

10.4028/www.scientific.net/msf.706-709.741 ◽

2012 ◽

Vol 706-709 ◽

pp. 741-744 ◽

Cited By ~ 1

Author(s):

Akio Kira ◽

Ryuichi Tomoshige ◽

Kazuyuki Hokamoto ◽

Masahiro Fujita

Keyword(s):

Phase Transformation ◽

Powdered Material ◽

Scanning Transmission Electron Microscope ◽

Ultrahigh Pressure ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission ◽

Metal Jet ◽

Very High

The various techniques of phase transformation of the material have been proposed by many researchers. We have developed several devices to generate the ultrahigh pressure by using high explosive. One of them uses metal jets. It is expected that the ultrahigh pressure occurs by the head-on collision between metal jets, because the velocity of the metal jet is very high. By mixing a powdered material with metal jets, the pressure of the material becomes high. The purpose of this study is to transform the phase of the powdered material by using this high pressure. The powders of the graphite and hBN were applied. The synthesis to the diamond and cBN was confirmed by X-ray diffraction (XRD). In this paper, the mechanism of the generation of the ultrahigh pressure is explained and the results of the observation of the powder by using scanning transmission electron microscope (STEM) are reported.

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Fabrication, characterization and magnetic properties of Na-doped ZnO nanorods

Functional Materials Letters ◽

10.1142/s1793604716500399 ◽

2016 ◽

Vol 09 (03) ◽

pp. 1650039 ◽

Cited By ~ 1

Author(s):

Jingyuan Piao ◽

Li-Ting Tseng ◽

Kiyonori Suzuki ◽

Jiabao Yi

Keyword(s):

Magnetic Measurements ◽

Zno Nanorods ◽

X Ray Diffraction ◽

Paramagnetic Resonance ◽

X Ray ◽

Shallow Donors ◽

Na Doping ◽

Transmission Electron ◽

Doped Zno ◽

Electron Paramagnetic

Na-doped ZnO nanorods have been fabricated through a hydrothermal method. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses indicate that the d spacing of ZnO increases with increasing doping concentration, suggesting the effective incorporation of dopant Na in the samples. Electron paramagnetic resonance (EPR) measurements indicate that there are shallow donors in pure ZnO samples and the shallow donors are strongly prohibited by Na doping. In addition, the resonance at g = 2.005 suggests the formation of Zn vacancies. Magnetic measurements indicate that pure ZnO is paramagnetic and Na doping leads to ferromagnetism at room temperature. Moreover, 0.5% Na-doped ZnO nanorods exhibits the largest saturation magnetization.

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New method for the production of bulk amorphous materials of Nd–Fe–B alloys

Journal of Materials Research ◽

10.1557/jmr.2005.0098 ◽

2005 ◽

Vol 20 (3) ◽

pp. 563-566 ◽

Cited By ~ 16

Author(s):

Tetsuji Saito ◽

Hiroyuku Takeishi ◽

Noboru Nakayama

Keyword(s):

Electron Microscopy ◽

Amorphous Materials ◽

Room Temperature ◽

Amorphous Structure ◽

X Ray Diffraction ◽

Bulk Materials ◽

X Ray ◽

Transmission Electron ◽

Melt Spun ◽

Melt Spun Ribbons

We report a new compression shearing method for the production of bulk amorphous materials. In this study, amorphous Nd–Fe–B melt-spun ribbons were successfully consolidated into bulk form at room temperature by the compression shearing method. X-ray diffraction and transmission electron microscopy studies revealed that the amorphous structure was well maintained in the bulk materials. The resultant bulk materials exhibited the same magnetic properties as the original amorphous Nd–Fe–B materials.

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A Chemical Solution Route to Rapid Synthesis of Homogeneous Bi100−xSbx Alloys Nanoparticles at Room Temperature

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2007.151 ◽

2007 ◽

Vol 7 (2) ◽

pp. 525-529 ◽

Cited By ~ 3

Author(s):

Bo Zhou ◽

Jun-Jie Zhu

Keyword(s):

Room Temperature ◽

Raw Materials ◽

X Ray Diffraction ◽

X Ray ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Solution Route ◽

Diffraction Patterns ◽

Co Reduction ◽

Chemical Solution Route

A chemical co-reduction route in aqueous solution was developed to synthesize Bi100−xSbx alloys at room temperature. The hydrolyses of Bi(III) and Sb(III) were effectively avoided by selecting proper raw materials and coordinator. X-ray diffraction analysis indicated that the as-prepared Bi100−xSbx alloys were homogeneous and phase-pure, and the Bi/Sb ratios in the alloys were very close to those in the aqueous solutions. The transmission electron microscope observation showed that the as-prepared Bi100−xSbx (x = 0∼100) alloys were particles with a size of tens of nanometers. The selected area electron diffraction patterns confirmed the high crystallinity, the homogeneousness, and the composition controllability of as-prepared alloys. All these characters and the nanometer-scaled size of the alloys are believed to be beneficial to the thermoelectric property of the Bi100−xSbx alloys.

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Effects of Bi Doping on the In15Sb85 Phase Change Recording Thin Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.47-50.813 ◽

2008 ◽

Vol 47-50 ◽

pp. 813-816

Author(s):

Sin Liang Ou ◽

Po Cheng Kuo ◽

Shu Chi Sheu ◽

Chih Hsiang Hsiao ◽

Don Yau Chiang ◽

...

Keyword(s):

Room Temperature ◽

X Ray Diffraction ◽

Crystallization Activation Energy ◽

Composite Target ◽

X Ray ◽

Transmission Electron ◽

Thermal Analyzer ◽

Crystallization Speed ◽

Bi Doping ◽

Si Wafer

The (In15Sb85)100-xBix films (x = 0~18.3) were deposited on nature oxidized Si wafer and glass substrate at room temperature by magnetron co-sputtering of Sb target and InBi composite target. The optical and thermal properties of the films were examined by reflectivity thermal analyzer. Microstructures of the films were analyzed by X-ray diffraction and transmission electron microscope. The crystallization activation energy of the (In15Sb85)100-xBix film (x = 0~18.3) was decreased with increasing Bi content, this indicated that the crystallization speed was improved by doping Bi. The structure of as-deposited (In15Sb85)100-xBix films was amorphous and it would transform to Sb, InSb, Bi, and BiIn2 coexisting phases after annealing at 250 °C for 30 min.

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