Study on Structural, Electrical and Optical Properties of Microcrystalline Si:H and SiC:H Films

1993 ◽  
Vol 297 ◽  
Author(s):  
F. Demichelis ◽  
G. Crovini ◽  
C.F. Pirri ◽  
E. Tresso ◽  
A. Rubino ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Electronic Transport ◽  
Transport Mechanisms ◽  
Conductivity Measurements ◽  
Electrical And Optical Properties ◽  
X Ray ◽  
Transmission Electron ◽  
Wide Range

We report results on a study on μc-Si:H and (μc-SiC:H films deposited by PECVD. The crystallinity fraction and the crystal sizes have been evaluated by X-ray diffractometry, Raman spectroscopy and Transmission Electron Microscopy(TEM). Infrared vibrational spectra of both μc-Si:H and |μc-SiC:H samples have been studied to obtain information on their structure. A comparison between the structure of the amorphous and diphasic amorphous-microcrystalline samples has been performed. Optical properties were obtained by transmission-reflectance and PDS measurements. Electronic transport mechanisms through the conductivity measurements in a wide range of temperatures (50-500 K) have been defined. Structural and electron density models have been discussed and used to interpret the experimental results.

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 In Situ and In Operando Techniques to Study Li-Ion and Solid-State Batteries: Micro to Atomic Level

Inorganics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 85
Author(s):  
Maryam Golozar ◽  
Raynald Gauvin ◽  
Karim Zaghib
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photoelectron Spectroscopy ◽  
Atomic Level ◽  
X Ray ◽  
In Situ Techniques ◽  
Transmission Electron ◽  
Wide Range ◽  
Li Ion

This work summarizes the most commonly used in situ techniques for the study of Li-ion batteries from the micro to the atomic level. In situ analysis has attracted a great deal of interest owing to its ability to provide a wide range of information about the cycling behavior of batteries from the beginning until the end of cycling. The in situ techniques that are covered are: X-ray diffraction (XRD), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and Scanning Transmission Electron Microscopy (STEM). An optimized setup is required to be able to use any of these in situ techniques in battery applications. Depending on the type of data required, the available setup, and the type of battery, more than one of these techniques might be needed. This study organizes these techniques from the micro to the atomic level, and shows the types of data that can be obtained using these techniques, their advantages and their challenges, and possible strategies for overcoming these challenges.

SYNTHESIS OF CdTe NANOPARTICLE BY γ-IRRADIATION

2002 ◽  
Vol 01 (05n06) ◽  
pp. 581-585
Author(s):  
SONG JA JO ◽  
YOUNG SOO KANG
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Γ Irradiation ◽  
X Ray ◽  
Pl Spectra ◽  
Cdte Nanoparticles ◽  
Transmission Electron

Semiconductor CdTe nanoparticles were synthesized by the γ-irradiation of Cd ion complex at room temperature. Cd-olate complex was reacted with aqueous NaHTe solution. The products were investigated by X-ray Powder Diffraction (XRD) and Transmission Electron Microscopy (TEM). The optical properties of CdTe were investigated with UV-vis and photoluminescence (PL) spectra.

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.

Synthesis and Optical Properties of L-Cysteine Hydrochloride-Stabilized CdSe Nanocrystals in a New Alkali System

2008 ◽  
Vol 8 (3) ◽  
pp. 1178-1182 ◽  
Author(s):  
Bin Feng ◽  
Feng Teng ◽  
Ai-Wei Tang ◽  
Yan Wang ◽  
Yan-Bing Hou ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Optical Properties ◽  
Photoelectron Spectroscopy ◽  
Water Soluble ◽  
Molar Ratio ◽  
Cdse Nanocrystals ◽  
X Ray ◽  
Transmission Electron ◽  
Cysteine Hydrochloride

Water-soluble CdSe nanocrystals were synthesized in a new alkali system at lower temperatures by using L-cysteine hydrochloride as a stabilizer and Na2SeSO3 as a selenium source to enable the synthesis of CdSe nanocrystals in a wider range of pHvalues. The CdSe nanocrystal powder was characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. We systematically investigated the effect of synthesis conditions on the optical properties of the L-cysteine hydrochloride-stabilized CdSe nanocrystals, and found that different sizes of CdSe nanocrystals can be obtained by changing the pHvalue, the molar ratio of L-cysteine hydrochloride to Cd2+, or the refluxing time. The emission maxima of the obtained CdSe nanocrystals can be tuned in a wider range from 477 to 575 nm by changing the pHvalue from 7 to 13. We observed an obvious blue-shift of the absorption and photoluminescence peak position by varying the molar ratio of L-Cys to Cd2+ from 3.5:1 to 2:1 at the same pHvalue. The size of the obtained nanocrystals increased and the full width at half maximum became narrower as reflux time increased. Transmission electron microscopy images indicate that the as-prepared CdSe nanocrystals have a good dispersion, which means that L-cysteine hydrochloride can control the grouping of CdSe nanocrystals excellently as a stabilizer in the new alkali system.

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.

scholarly journals High Quality Growth of Cobalt Doped GaN Nanowires with Enhanced Ferromagnetic and Optical Response

Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3537
Author(s):  
Mudassar Maraj ◽  
Ghulam Nabi ◽  
Khurram Usman ◽  
Engui Wang ◽  
Wenwang Wei ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Magnetic Properties ◽  
Optical Properties ◽  
Synthesis Process ◽  
Cobalt Doping ◽  
Si Substrate ◽  
X Ray ◽  
Gan Nanowires ◽  
Transmission Electron

Group III–V semiconductors with direct band gaps have become crucial for optoelectronic and microelectronic applications. Exploring these materials for spintronic applications is an important direction for many research groups. In this study, pure and cobalt doped GaN nanowires were grown on the Si substrate by the chemical vapor deposition (CVD) method. Sophisticated characterization techniques such as X-ray diffraction (XRD), Scanning Electron Microscope (SEM), Energy Dispersive X-Ray Spectroscopy (EDS), Transmission Electron Microscopy (TEM), High-Resolution Transmission Electron Microscopy (HRTEM) and photoluminescence (PL) were used to characterize the structure, morphology, composition and optical properties of the nanowires. The doped nanowires have diameters ranging from 60–200 nm and lengths were found to be in microns. By optimizing the synthesis process, pure, smooth, single crystalline and highly dense nanowires have been grown on the Si substrate which possess better magnetic and optical properties. No any secondary phases were observed even with 8% cobalt doping. The magnetic properties of cobalt doped GaN showed a ferromagnetic response at room temperature. The value of saturation magnetization is found to be increased with increasing doping concentration and magnetic saturation was found to be 792.4 µemu for 8% cobalt doping. It was also depicted that the Co atoms are substituted at Ga sites in the GaN lattice. Furthermore N vacancies are also observed in the Co-doped GaN nanowires which was confirmed by the PL graph exhibiting nitrogen vacancy defects and strain related peaks at 455 nm (blue emission). PL and magnetic properties show their potential applications in spintronics.

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.

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.

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