Structural and Optical Properties of Ge Nanocrystals Embedded in Al2O3

2008 ◽  
Vol 8 (2) ◽  
pp. 572-576 ◽  
Author(s):  
P. Caldelas ◽  
A. G. Rolo ◽  
A. Chahboun ◽  
S. Foss ◽  
S. Levichev ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Rf Magnetron Sputtering ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Transmission Electron ◽  
Xrd Techniques ◽  
Ge Nanocrystals

Ge nanocrystals (NCs) embedded in aluminum oxide were grown by RF-magnetron sputtering. Raman, high resolution transmission electron microscopy (HRTEM), selected area diffraction (SAD), and X-ray diffraction (XRD) techniques confirmed good cristallinity of the NCs from samples annealed at 800 °C. The average NC size was estimated to be around 7 nm. Photoluminescence (PL) measurements show an emission related to the NCs. The temperature dependence of the PL confirms the confinement phenomenon in the Ge NCs.

Optical Properties of Nanostructured Mesoporous Semiconductor Films

2004 ◽  
Vol 822 ◽  
Author(s):  
Iris Nandhakumar ◽  
Timothy Gabriel ◽  
Xiahong Li ◽  
George S. Attard ◽  
Matthew Markham ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Liquid Crystal ◽  
Reflectance Spectroscopy ◽  
Semiconductor Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Liquid Crystal Templating

AbstractDirect liquid crystal templating from non-ionic polyoxyethylene surfactants has been utilised to produce well-defined birefringent films of nanostructured cadmium telluride with mesoporous architectures of extended spatial periodicities. The template mixtures and films were characterised by X-ray diffraction, transmission electron microscopy and polarising optical microscopy to ascertain the presence of a regular nanostructure. UV-VIS reflectance spectroscopy was employed to investigate the films' optical properties.

scholarly journals Cottonseed Oilcake Extract Mediated Green Synthesis of Silver Nanoparticles and Its Antibacterial and Cytotoxic Activity

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Muthusamy Govarthanan ◽  
Min Cho ◽  
Jung-Hee Park ◽  
Jum-Suk Jang ◽  
Young-Joo Yi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Silver Nanoparticles ◽  
Fourier Transform ◽  
Green Synthesis ◽  
Pseudomonas Syringae ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Xrd Techniques

Agroindustrial byproduct mediated green synthesis of silver nanoparticles was carried out using cottonseed oilcake (CSOC) extract. The aqueous silver nitrate formed stable silver nanoparticles with CSOC extract as a reducing agent for Ag+to Ag0. The synthesized nanoparticles were characterized using energy dispersive X-ray spectroscopy (EDS), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) techniques. The synthesized silver nanoparticles (AgNPs) (4 mM) significantly inhibited the growth of phytopathogens,Pseudomonas syringaepv.actinidiaeandRalstonia solanacearum. Further, cytotoxicity of AgNPs was evaluated using rat splenocyte cells. The splenocyte viability was decreased according to the increasing concentration of AgNPs and 90% of cell death was observed at 100 μg/mL.

Optical and photocatalytic properties of photoactive paper with polycrystalline TiO2 nanopigment for optimal product design

TAPPI Journal ◽  
2012 ◽  
Vol 11 (5) ◽  
pp. 33-38 ◽  
Author(s):  
SEONGHYUK KO ◽  
PAUL D. FLEMING ◽  
MARGARET JOYCE ◽  
PNINA ARI-GUR
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Gas Chromatography ◽  
Titanium Dioxide ◽  
Optical Properties ◽  
Photocatalytic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Optimal Product Design

We investigated the effect of the crystalline phases of titanium dioxide nanopigment to optimize the optical properties and photocatalytic activity for synthesizing a photoactive paper. Six different ratios of anatase to rutile were prepared. Phase change and particle size were characterized using X-ray diffraction and transmission electron microscopy. Optical properties including opacity and brightness were tested. Photocatalytic activity was evaluated by measuring toluene decomposition, using gas chromatography. A specific ratio between two different crystallites of titanium dioxide showed relatively better optical and photoactive properties. The optimal anatase-to-rutile ratio was found to be 0.52:0.48.

scholarly journals Effect of annealing temperature on the structural, morphological and optical properties of TiO2 nanotubes and their composites with CdSe Quantum dots

2019 ◽  
Vol 17 (2) ◽  
Author(s):  
Tani Vats ◽  
Shailesh N. Sharma
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Quantum Dots ◽  
Optical Properties ◽  
Tio2 Nanotubes ◽  
Annealing Temperature ◽  
Cdse Quantum Dots ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron

In the present work we have synthesized Titanium dioxide (TiO2) nanotubes using hydrothermal method, and studied the effect of annealing temperature on the crystalinity of the nanotubes. The nanotubes obtained were annealed at 400o C and 600o C. In order to elucidate the changes caused by the annealing temperature transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD) were used. The composites of titania nanotubes and CdSe quantum dots were prepared using bifunctional linker, mercaptopropionic acid. The nanocomposites were characterized using TEM and XDR. The optical propierties of the modified TiO2 nanotubes and their composites with CdSe (for potential solar cell applications) were characterized by UV-Vis absorption spectra and photoluminescence (PL) spectra.

Soft-Template Synthesis of Single-Crystalline CdS Dendrites

2006 ◽  
Vol 6 (1) ◽  
pp. 162-167 ◽  
Author(s):  
Haixia Niu ◽  
Qing Yang ◽  
Kaibin Tang ◽  
Yi Xie ◽  
Yongchun Zhu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Soft Template ◽  
X Ray Diffraction ◽  
Single Crystalline ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

The single-crystalline CdS dendrites have been fabricated from the reaction of CdCl2 and thiourea at 180 °C, in which glycine was employed as a soft template. The obtained products were explored by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and selected area electronic diffraction. The optical properties of CdS dendrites have been investigated by ultraviolet and visible light (UV-vis) and photoluminescence techniques. The investigations indicated that the dendrites were grown due to the anisotropic properties enhanced by the use of Glycine in the route.

Influence of Ammoniating Temperatures on Microstructures, Morphologies and Optical Properties of GaN/Nb Nanostructures by RF Magnetron Sputtering Technique

2012 ◽  
Vol 1439 ◽  
pp. 17-23
Author(s):  
Feng Shi ◽  
Chengshan Xue
Keyword(s):  
Electron Microscopy ◽  
Optical Properties ◽  
Magnetron Sputtering ◽  
Photoelectron Spectroscopy ◽  
Hexagonal Wurtzite Structure ◽  
Rf Magnetron Sputtering ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gan Nanowires ◽  
Transmission Electron

AbstractGaN nanowires and nanorods have been successfully synthesized on Si (111) substrates by magnetron sputtering through ammoniating Ga2O3/Nb thin films and the effects of ammoniation temperatures on growth of GaN nanowires and nanorods were analyzed in detail. X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, and photoluminescence spectra were carried out to characterize microstructures, morphologies, and optical properties of GaN samples. The results demonstrate that sample after ammoniation at 950 °C is single crystal GaN with hexagonal wurtzite structure and high crystalline quality, having the size of 30 - 80 nm in diameter. After ammoniation at 1000 °C, GaN nanorods appear with smooth and clean surface and more than 100 nm in diameter. The optical properties of GaN nanowires grown at 950 °C and nanorods grown at 1000 °C are best with strong emission intensities.

Facile One-Pot Synthesis and Optical Properties of Quinary Wurtzite Cu3ZnInSnS6 Nanocrystals

NANO ◽  
2016 ◽  
Vol 11 (11) ◽  
pp. 1650130
Author(s):  
Dehui Li ◽  
Chen Zhang ◽  
Yajie Zhang ◽  
Weichen Qi ◽  
Jinxiang Dong ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Energy Dispersive Spectrometry ◽  
Main Body ◽  
X Ray Diffraction ◽  
One Pot ◽  
X Ray ◽  
Transmission Electron ◽  
Nir Absorption

Nearly monodisperse bullet-like Cu3ZnInSnS6 (CZITS) nanocrystals with wurtzite structure were successfully synthesized through optimized noninjection method. The structure, composition, morphology and optical properties of CZITS nanocrystals were characterized by X-ray diffraction, energy dispersive spectrometry, transmission electron microscopy and UV-Vis–NIR absorption. Their suitable bandgap and photoresponsive behavior indicate a high potential application in the field of solar cells. The growth mechanism of the as-synthesized CZITS nanocrystals was preliminarily discussed. It was found that the formation of CZITS could be separated into two steps: nucleation of Cu7S4 and growth of the CZITS main body.

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

1982 ◽  
Vol 40 ◽  
pp. 722-723 ◽  
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.

scholarly journals 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 ◽  
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.

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

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...

Sign in / Sign up

Export Citation Format

Share Document