Thermally Evaporated In2O3 Nanoloquats with Tunable Broad-Band Emissions

We describe synthesis of In2O3 nanoloquats grown by thermal evaporation under different oxygen flow rates and temperatures. Gold nanoparticles were used the catalysts and were dispersed on the silicon wafer to assist growth of In2O3 nanoloquats. The nanostructures of In2O3 nanoloquats were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The photoluminescence study reveals that In2O3 nanoloquats could emit different broad-band luminescence peaks in the range of 410∼620 nm by tuning different oxygen flow rates and temperatures. The wide tuning range in the emission peaks of In2O3 nanoloquats has potential in applications of white light illumination.

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Simplified Synthesis and Luminous Mechanism of Eu2+-Doped α-Si3N4 Nanowires with Strong Green Luminescent Properties

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.727.635 ◽

2017 ◽

Vol 727 ◽

pp. 635-641 ◽

Cited By ~ 3

Author(s):

Rui Su ◽

Zhi Feng Huang ◽

Fei Chen ◽

Qiang Shen ◽

Lian Meng Zhang

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Broad Band ◽

Luminescent Properties ◽

X Ray Diffraction ◽

X Ray ◽

Broad Band Emission ◽

Band Emission ◽

Nitridation Process ◽

Transmission Electron

Ultra-long, single crystal, Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350 °C for 4 h. Phases, chemical composition and microcosmic feature of cryomilled powders and as-prepared nanowires were tested by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), respectively. The results suggested that Eu was successfully introduced into Si lattice after the cryomilling process and then entered into the lattice of α-Si3N4 during the nitridation process. The as-synthesized Eu-doped α-Si3N4 nanowires had highly uniform dimension with 20~30 nm in diameter and ~100 μm in length. The room temperature photoluminescence (PL) spectrum of as-synthesized nanowires showed a broad band emission center at 570 nm which was attributed to the transition from 4f65d to 4f7 in Eu2+. The transition from Eu3+ to Eu2+ during nitridation process was tested by X-ray photoelectron spectroscopy (XPS).

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Piezoelectric Material for High Efficiency Ultrasonic Siren

Materials Science Forum ◽

10.4028/www.scientific.net/msf.514-516.225 ◽

2006 ◽

Vol 514-516 ◽

pp. 225-229

Author(s):

Elena Dimitriu ◽

Alin Iuga

Keyword(s):

Electron Microscopy ◽

High Efficiency ◽

Sintered Material ◽

Broad Band ◽

Radial Mode ◽

X Ray Diffraction ◽

X Ray ◽

Acoustical Emission ◽

Transmission Electron ◽

Dielectric And Piezoelectric Properties

A PZT-type material, doped with niobium and lithium was prepared by the ceramic technique. The microstructure of the sintered material at 1280oC was performed by scanning electron microscopy (SEM), transmission electron microscopy and by X-ray diffraction. Dielectric and piezoelectric properties were measured. The good planar properties of the material made it possible to obtain ceramic disks with a strong radial mode. Two such disks, glued together, with opposed polarisation constitute a bimorf element, which successfully converts the radial mode into a flexural one. At the center of the bimorf a conical acoustical impedance adapter is fixed in order to increase the frontal acoustical emission of the device. This ultrasonic device provides a broad – band, high acoustical emission, and is suitable to work as a high efficiency ultrasonic siren. It can be used in intruder alarm devices, ultrasonic telemeters.

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A High Resolution Study of G.P. Zones in Aluminum - 4.2 at % Silver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055904 ◽

1982 ◽

Vol 40 ◽

pp. 722-723 ◽

Cited By ~ 1

Author(s):

R. Gronsky

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

High Resolution ◽

Computer Simulations ◽

Structural Characteristics ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Resolution Study

The phenomenon of clustering in Al-Ag alloys has been extensively studied since the early work of Guinierl, wherein the pre-precipitation state was characterized as an assembly of spherical, ordered, silver-rich G.P. zones. Subsequent x-ray and TEM investigations yielded results in general agreement with this model. However, serious discrepancies were later revealed by the detailed x-ray diffraction - based computer simulations of Gragg and Cohen, i.e., the silver-rich clusters were instead octahedral in shape and fully disordered, atleast below 170°C. The object of the present investigation is to examine directly the structural characteristics of G.P. zones in Al-Ag by high resolution transmission electron microscopy.

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Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

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The Effect of the Microstructure of Diffusion Barriers on the Palladium Activation for Electroless Copper Deposition

MRS Proceedings ◽

10.1557/proc-716-b11.20 ◽

2002 ◽

Vol 716 ◽

Author(s):

Seok Woo Hong ◽

Yong Sun Lee ◽

Ki-Chul Park ◽

Jong-Wan Park

Keyword(s):

Electron Microscopy ◽

Diffusion Barriers ◽

Copper Deposition ◽

X Ray Diffraction ◽

Plan View ◽

X Ray ◽

Transmission Electron ◽

Electroless Copper ◽

Sheet Resistance Measurement ◽

Scanning Electron

AbstractThe effect of microstructure of dc magnetron sputtered TiN and TaN diffusion barriers on the palladium activation for autocatalytic electroless copper deposition has been investigated by using X-ray diffraction, sheet resistance measurement, field emission scanning electron microscopy (FE-SEM) and plan view transmission electron microscopy (TEM). The density of palladium nuclei on TaN diffusion barrier increases as the grain size of TaN films decreases, which was caused by increasing nitrogen content in TaN films. Plan view TEM results of TiN and TaN diffusiton barriers showed that palladium nuclei formed mainly on the grain boundaries of the diffusion barriers.

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Palladium Nanowire Thin Films via Template Growth

MRS Proceedings ◽

10.1557/proc-775-p4.7 ◽

2003 ◽

Vol 775 ◽

Author(s):

Donghai Wang ◽

David T. Johnson ◽

Byron F. McCaughey ◽

J. Eric Hampsey ◽

Jibao He ◽

...

Keyword(s):

Thin Film ◽

Electron Microscopy ◽

Thin Films ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Conductive Substrate ◽

Palladium Nanowires ◽

Efficient Route ◽

Silica Thin Film

AbstractPalladium nanowires have been electrodeposited into mesoporous silica thin film templates. Palladium continually grows and fills silica mesopores starting from a bottom conductive substrate, providing a ready and efficient route to fabricate a macroscopic palladium nanowire thin films for potentially use in fuel cells, electrodes, sensors, and other applications. X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicate it is possible to create different nanowire morphology such as bundles and swirling mesostructure based on the template pore structure.

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Quartz Crystallite Size and Moganite Content as Indicators of the Mineralogical Maturity of the Carboniferous Chert: The Case of Cherts from Eastern Asturias (Spain)

Minerals ◽

10.3390/min11060611 ◽

2021 ◽

Vol 11 (6) ◽

pp. 611

Author(s):

Celia Marcos ◽

María de Uribe-Zorita ◽

Pedro Álvarez-Lloret ◽

Alaa Adawy ◽

Patricia Fernández ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Crystallite Size ◽

Archaeological Sites ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Infrared And Raman Spectroscopy ◽

First Time ◽

Geological Formations

Chert samples from different coastal and inland outcrops in the Eastern Asturias (Spain) were mineralogically investigated for the first time for archaeological purposes. X-ray diffraction, X-ray fluorescence, transmission electron microscopy, infrared and Raman spectroscopy and total organic carbon techniques were used. The low content of moganite, since its detection by X-ray diffraction is practically imperceptible, and the crystallite size (over 1000 Å) of the quartz in these cherts would be indicative of its maturity and could potentially be used for dating chert-tools recovered from archaeological sites. Also, this information can constitute essential data to differentiate the cherts and compare them with those used in archaeological tools. However, neither composition nor crystallite size would allow distinguishing between coastal and inland chert outcrops belonging to the same geological formations.

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Effect of synthesis and activation methods on the character of CoMo/ultrastable Y-zeolite catalysts

Open Chemistry ◽

10.1515/chem-2021-0064 ◽

2021 ◽

Vol 19 (1) ◽

pp. 745-754

Author(s):

Khoirina Dwi Nugrahaningtyas ◽

Eddy Heraldy ◽

Rachmadani ◽

Yuniawan Hidayat ◽

Indriana Kartini

Keyword(s):

Electron Microscopy ◽

Reduction Process ◽

Particle Morphology ◽

Zeolite Catalysts ◽

X Ray Diffraction ◽

Y Zeolite ◽

X Ray ◽

Irregular Particle ◽

Transmission Electron ◽

Pure Metals

Abstract The properties of three types of CoMo/USY catalysts with different synthesized methods have been studied. The sequential and co-impregnation methods followed by activation using calcination and reduction process have been conducted. The properties of the catalysts were examined using Fourier-transform-infrared (FTIR) spectroscopy, X-ray diffraction (XRD) with refinement, and surface area analyzer (SAA). The FTIR spectrum study revealed the enhanced intensity of its Bronsted acid site, and the XRD diffractogram pattern verified the composition of pure metals, oxides, and alloys in the catalyst. The SAA demonstrated the mesoporous features of the catalyst. Scanning electron microscopy showed an irregular particle morphology. Additional analysis using the transmission electron microscopy indicated that the metal has successfully impregnated without damaging the USY structure.

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Controlled Synthesis of CuS and Cu9S5 and Their Application in the Photocatalytic Mineralization of Tetracycline

Catalysts ◽

10.3390/catal11080899 ◽

2021 ◽

Vol 11 (8) ◽

pp. 899

Author(s):

Murendeni P. Ravele ◽

Opeyemi A. Oyewo ◽

Damian C. Onwudiwe

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Blue Shift ◽

X Ray Diffraction ◽

X Ray ◽

Copper Sulfides ◽

Transmission Electron ◽

Single Source Precursor ◽

Pure Phase ◽

Pure Phases

Pure-phase Cu2−xS (x = 1, 0.2) nanoparticles have been synthesized by the thermal decomposition of copper(II) dithiocarbamate as a single-source precursor in oleylamine as a capping agent. The compositions of the Cu2−xS nanocrystals varied from CuS (covellite) through the mixture of phases (CuS and Cu7.2S4) to Cu9S5 (digenite) by simply varying the temperature of synthesis. The crystallinity and morphology of the copper sulfides were studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), which showed pure phases at low (120 °C) and high (220 °C) temperatures and a mixture of phases at intermediate temperatures (150 and 180 °C). Covellite was of a spherical morphology, while digenite was rod shaped. The optical properties of these nanocrystals were characterized by UV−vis–NIR and photoluminescence spectroscopies. Both samples had very similar absorption spectra but distinguishable fluorescence properties and exhibited a blue shift in their band gap energies compared to bulk Cu2−xS. The pure phases were used as catalysts for the photocatalytic degradation of tetracycline (TC) under visible-light irradiation. The results demonstrated that the photocatalytic activity of the digenite phase exhibited higher catalytic degradation of 98.5% compared to the covellite phase, which showed 88% degradation within the 120 min reaction time using 80 mg of the catalysts. The higher degradation efficiency achieved with the digenite phase was attributed to its higher absorption of the visible light compared to covellite.

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Multi-scale Investigation of Heterogeneous Swift Heavy Ion Tracks in Stannate Pyrochlore

Journal of Materials Chemistry A ◽

10.1039/d1ta04924k ◽

2021 ◽

Author(s):

Eric O'Quinn ◽

Cameron Tracy ◽

William F. Cureton ◽

Ritesh Sachan ◽

Joerg C. Neuefeind ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Heavy Ion ◽

X Ray Diffraction ◽

X Ray ◽

Structural Modifications ◽

Multi Scale ◽

Ion Tracks ◽

Swift Heavy Ion ◽

Transmission Electron

Er2Sn2O7 pyrochlore was irradiated with swift heavy Au ions (2.2 GeV), and the induced structural modifications were systematically examined using complementary characterization techniques including transmission electron microscopy (TEM), X-ray diffraction...

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