Liquid Phase Epitaxy of Si1−xGex(O<×≲1) On Partially Masked Si-Substrates

ABSTRACTSingle-crystal Si1−x Gex(O<×≲1) layers are grown by seeded growth on partially SiO2-masked Si-substrates, using a one-step liquid phase epitaxy (LPE) process. The seed regions are stripe- and hole-shaped windows in the oxide, having linear dimensions between 1.5 and 100 μm. The windows extend in different orientation on (111) and (100) orientated substrates. Lateral overgrowth over the oxide-masked areas is achieved up to 70 μm in <110>-directions. X-ray diffraction and Raman scattering show that the epitaxial islands are homogeneous and of excellent crystal quality. In the regions of lateral overgrowth the dislocation density is reduced considerably as shown by defect-etching and cross section transmission electron microscopy.

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High-Quality GaInAsSb and GaAlAsSb Layers for Thermophotovoltaics Grown by Liquid-Phase Epitaxy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.159.87 ◽

2010 ◽

Vol 159 ◽

pp. 87-90

Author(s):

M. Milanova ◽

Roumen Kakanakov ◽

G. Koleva ◽

P. Vitanov ◽

V. Bakardjieva ◽

...

Keyword(s):

Liquid Phase ◽

Liquid Phase Epitaxy ◽

X Ray Diffraction ◽

High Quality ◽

X Ray ◽

Al Content ◽

Quaternary Compounds ◽

Transmission Electron

GaSb based III-V heterostuctures are attractive for optoelectronic devices such as midin- frared lasers, detectors, and thermophotovoltaics (TPVs). In this paper the growth and characterization of GaInAsSb and GaAlAsSb quaternary layers, lat-tice-matched to GaSb substrate, are reported, with a particular focus on these alloys for TPV devi-ces. High-quality with a mirror-like surface morphology epilayers Ga1-x InxAsy Sb1-y with In content x in the range 0.1-0.22 and Ga1-xAlxAsySb1-y layers with Al content up to 0.3 in the solid are grown by Liquid-Phase Epitaxy (LPE) from In- and Ga-rich melt, respectively. The compositions of the quaternary compounds are determined by X-ray microanalysis. The crystalline quality of GaInAsSb/ GaSb and GaAlAsSb/GaSb heterostuctures is studied by X-ray diffraction (XRD) and transmission electron microscopy (TEM) measurements.

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One Step Synthesis and Characterization of Zirconia-Graphene Composites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.600.174 ◽

2012 ◽

Vol 600 ◽

pp. 174-177 ◽

Cited By ~ 1

Author(s):

Jian Fei Xia ◽

Zong Hua Wang ◽

Yan Zhi Xia ◽

Fei Fei Zhang ◽

Fu Qiang Zhu ◽

...

Keyword(s):

Synthesis And Characterization ◽

Two Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Graphene Composite ◽

Transmission Electron ◽

One Step ◽

Ft Ir ◽

Xrd Techniques

Zirconia-graphene composite (ZrO2-G) has been successfully synthesized via decomposition of ZrOCl2•6H2O in a water-isopropanol system with dispersed graphene oxide (GO) utilizing Na2S as a precursor could enable the occurrence of the deposition of Zr4+ and the deoxygenation of GO at the same time. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) techniques were used to characterize the samples. It was found that graphene were fully coated with ZrO2, and the ZrO2 existing in tetragonal phase, which resulted in the formation of two-dimensional composite.

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Low-temperature hydrothermal synthesis of hierarchical flower-like CuB2O4 superstructures

Processing and Application of Ceramics ◽

10.2298/pac2002113u ◽

2020 ◽

Vol 14 (2) ◽

pp. 113-118

Author(s):

Daniel Ursu ◽

Anamaria Dabici ◽

Marinela Miclau ◽

Nicolae Miclau

Keyword(s):

Thermal Stability ◽

Low Temperature ◽

Self Assembly ◽

Hydrothermal Solution ◽

Optical Measurements ◽

Oriented Attachment ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

One Step

We report for the first time the fabrication of hierarchical ordered superstructure CuB2O4 with flower-like morphology via a one-step, low temperature hydrothermal method. The tetragonal structure of CuB2O4 was determined by X-ray diffraction and high-resolution transmission electron microscopy. Optical measurements attested of the quality of the fabricated CuB2O4 and high temperature X-ray diffraction confirmed its thermal stability up to 600 ?C. The oriented attachment growth and the hierarchical self-assembly of micrometer-sized platelets producing hierarchical superstructures with flower-like morphology are designed by pH of the hydrothermal solution. The excellent band gap, high thermal stability and hierarchical structure of the CuB2O4 are promising for the photovoltaic and photocatalytic applications.

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X‐ray diffraction studies of the epitaxy ofa/b‐axes oriented YBa2Cu3O7−δfilms grown by liquid phase epitaxy

Journal of Applied Physics ◽

10.1063/1.355722 ◽

1994 ◽

Vol 75 (10) ◽

pp. 5243-5248 ◽

Cited By ~ 21

Author(s):

F. Sandiumenge ◽

C. Dubs ◽

P. Görnert ◽

S. Galí

Keyword(s):

Liquid Phase ◽

Liquid Phase Epitaxy ◽

X Ray Diffraction ◽

X Ray

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Epitaxial Growth of Aluminum Nitride on Sapphire and Silicon

MRS Proceedings ◽

10.1557/proc-358-1023 ◽

1994 ◽

Vol 358 ◽

Cited By ~ 1

Author(s):

K. Dovidenko ◽

S. Oktyabrsky ◽

J. Narayan ◽

M. Razeghi

Keyword(s):

Epitaxial Growth ◽

Substrate Surface ◽

Wide Band ◽

X Ray Diffraction ◽

Wide Band Gap ◽

High Quality ◽

Microstructural Characteristics ◽

X Ray ◽

Si Substrates ◽

Transmission Electron

ABSTRACTThe microstructural characteristics of wide band gap semiconductor, hexagonal A1N thin films on Si(100), (111), and sapphire (0001) and (10ī2) were studied by transmission electron microscopy (TEM) and x-ray diffraction. The films were grown by MOCVD from TMA1 + NH3 + N2 gas mixtures. Different degrees of film crystallinity were observed for films grown on α-A12O3 and Si substrates in different orientations. The epitaxial growth of high quality single crystalline A1N film on (0001) α-Al2O3 was demonstrated with a dislocation density of about 2*10 10cm−2 . The films on Si(111) and Si(100) substrates were textured with the c-axis of A1N being perpendicular to the substrate surface.

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A facile synthesis of a carbon-encapsulated Fe3O4 nanocomposite and its performance as anode in lithium-ion batteries

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.4.79 ◽

2013 ◽

Vol 4 ◽

pp. 699-704 ◽

Cited By ~ 18

Author(s):

Raju Prakash ◽

Katharina Fanselau ◽

Shuhua Ren ◽

Tapan Kumar Mandal ◽

Christian Kübel ◽

...

Keyword(s):

Electron Microscopy ◽

Lithium Ion ◽

Iron Pentacarbonyl ◽

X Ray Diffraction ◽

Facile Synthesis ◽

X Ray ◽

Transmission Electron ◽

Lithium Ion Cell ◽

Carbon Framework ◽

One Step

A carbon-encapsulated Fe3O4 nanocomposite was prepared by a simple one-step pyrolysis of iron pentacarbonyl without using any templates, solvents or surfactants. The structure and morphology of the nanocomposite was investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller analysis and Raman spectroscopy. Fe3O4 nanoparticles are dispersed intimately in a carbon framework. The nanocomposite exhibits well constructed core–shell and nanotube structures, with Fe3O4 cores and graphitic shells/tubes. The as-synthesized material could be used directly as anode in a lithium-ion cell and demonstrated a stable capacity, and good cyclic and rate performances.

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Activation of persulfate by heterogeneous catalyst ZnCo2O4–RGO for efficient degradation of bisphenol A

Canadian Journal of Chemistry ◽

10.1139/cjc-2020-0192 ◽

2020 ◽

Vol 98 (12) ◽

pp. 771-778

Author(s):

Xin Chang ◽

Xiangyang Xu ◽

Zhifeng Gao ◽

Yingrui Tao ◽

Yixuan Yin ◽

...

Keyword(s):

Electron Microscopy ◽

Bisphenol A ◽

Photoelectron Spectroscopy ◽

X Ray Diffraction ◽

Reaction Conditions ◽

X Ray ◽

Transmission Electron ◽

Nucleation Sites ◽

One Step ◽

Application Potential

A nanocomposite, reduced graphene oxide (RGO) modified ZnCo2O4 (ZnCo2O4–RGO) was synthesized via one-step solvothermal method for activating persulfate (PS) to degrade bisphenol A (BPA). The morphology and structure of the nanocomposite were identified by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. RGO provides nucleation sites for ZnCo2O4 to grow and inhibits the agglomeration of the nanoparticles. The influence of different reaction conditions on the oxidation of BPA catalyzed by ZnCo2O4–RGO was investigated, including the content of RGO, the dosage of catalyst, the concentration of humic acid (HA), anions in the environment, the reaction temperature, and pH. BPA can be totally degraded within 20 min under optimized reaction conditions. The presence of HA, Cl−, and NO3− only has a slight effect on the oxidation of BPA, whereas the presence of either H2PO4− or HCO3− can greatly inhibit the reaction. ZnCo2O4–RGO shows good cycling stability and practical application potential. A reaction mechanism of the degradation of BPA was also explored.

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Hydrothermal Synthesis of rGO/PbTiO3 Photocatalyst and Its Photocatalytic H2 Evolution Activity

Journal of Nanomaterials ◽

10.1155/2019/4869728 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Chunyan Wang ◽

Lianwei Shan ◽

Dongyuan Song ◽

Yanwei Xiao ◽

Jagadeesh Suriyaprakash

Keyword(s):

Photocatalytic Performance ◽

H2 Evolution ◽

X Ray Diffraction ◽

Hydrothermal Route ◽

X Ray ◽

Transmission Electron ◽

Reduced Graphene ◽

Efficient Charge ◽

One Step ◽

Photocatalytic H2 Evolution

In this letter, we investigated the photocatalytic activity of the newly formed rGO/PbTiO3 composites, which are synthesized by a one-step hydrothermal route. By adjusting the amount of reduced graphene oxide (rGO) (0, 0.15, 0.30, 0.60, and 1.20 wt%) with the PbTiO3, we constructed various photocatalysts for this investigation. The crystal structure and morphology of the various composites were studied by powder X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). Photoelectron spectroscopic study revealed that the band structure of the newly formed composites and efficient charge separation can be obtained by the interfaces of various rGO content. In addition, the photocatalytic performance of the synthesized composites was explored by H2 evolution and rhodamine blue (RhB) degradation. The obtained results indicated that the addition of the appropriate amount of rGO could improve the activity of pure PbTiO3, significantly.

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Facile hydrothermal synthesis of ternary CeO2–SnO2/rGO nanocomposite for supercapacitor application

Functional Materials Letters ◽

10.1142/s1793604720510054 ◽

2020 ◽

Vol 13 (02) ◽

pp. 2051005 ◽

Cited By ~ 4

Author(s):

Godlaveeti Sreenivasa Kumar ◽

Somala Adinarayana Reddy ◽

Hussen Maseed ◽

Nagireddy Ramamanohar Reddy

Keyword(s):

Electron Microscope ◽

Specific Capacitance ◽

High Performance ◽

High Specific Capacitance ◽

Energy Storage And Conversion ◽

X Ray Diffraction ◽

X Ray ◽

Supercapacitor Application ◽

Transmission Electron ◽

One Step

In this work, we present the synthesis of a ternary CeO2–SnO2/rGO nanocomposite by using a facile one-step hydrothermal method. The as-synthesized composite was structural, chemical, morphological, elemental information studied by using different characterization techniques X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDAX) and transmission electron microscope (TEM). The CeO2–SnO2/rGO exhibited an excellent specific capacitance of 156[Formula: see text]F[Formula: see text][Formula: see text] at 0.5[Formula: see text]A/g in the presence of 3 M KOH solution. The synergic effect of CeO2, SnO2 and graphene composite coated on Ni foam endowed a high specific capacitance than their individual compounds. This work suggests that the novel ternary composite is a promising candidate for the high performance electrochemical energy storage and conversion systems.

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