Investigation of graphene oxide-hydrogen interaction using in-situ X-ray diffraction studies

The graphene oxide/Fe3O4 composites were prepared by in situ precipitation method in this article. The microstructure and surface morphology of composites were characterized by Fourier transform infrared spectrum, X-ray diffraction and scanning electron microscopy, respectively. Cyclic voltammetry was employed for the determination of specific capacitance and other electrochemical performances. It was shown that there was the chemical bonding force between GO and Fe3O4 particles. And the surfaces of GO were wrapped by the Fe3O4 particles precipitated on the surfaces of GO sheets and no impurities were detected. Furthermore, the specific capacitance of GO/Fe3O4 composite electrodes decreased as Fe3O4 particles reduced and the redox peaks became weaker owing to the addition of nonconductive Fe3O4 particles.

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Superflexibility of graphene oxide

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1605121113 ◽

2016 ◽

Vol 113 (40) ◽

pp. 11088-11093 ◽

Cited By ~ 51

Author(s):

Philippe Poulin ◽

Rouhollah Jalili ◽

Wilfrid Neri ◽

Frédéric Nallet ◽

Thibaut Divoux ◽

...

Keyword(s):

Graphene Oxide ◽

Unique Feature ◽

Bending Rigidity ◽

X Ray Diffraction ◽

Synchrotron Source ◽

X Ray ◽

Bending Modulus ◽

Bendable Electronics ◽

Very High

Graphene oxide (GO), the main precursor of graphene-based materials made by solution processing, is known to be very stiff. Indeed, it has a Young’s modulus comparable to steel, on the order of 300 GPa. Despite its very high stiffness, we show here that GO is superflexible. We quantitatively measure the GO bending rigidity by characterizing the flattening of thermal undulations in response to shear forces in solution. Characterizations are performed by the combination of synchrotron X-ray diffraction at small angles and in situ rheology (rheo-SAXS) experiments using the high X-ray flux of a synchrotron source. The bending modulus is found to be 1kT, which is about two orders of magnitude lower than the bending rigidity of neat graphene. This superflexibility compares with the fluidity of self-assembled liquid bilayers. This behavior is discussed by considering the mechanisms at play in bending and stretching deformations of atomic monolayers. The superflexibility of GO is a unique feature to develop bendable electronics after reduction, films, coatings, and fibers. This unique combination of properties of GO allows for flexibility in processing and fabrication coupled with a robustness in the fabricated structure.

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In-situ hybridization of ZnO nanorod and graphene oxide with enhancing photocatalytic activity

Vietnam Journal of Catalysis and Adsorption ◽

10.51316/jca.2021.020 ◽

2021 ◽

Vol 10 (1) ◽

pp. 122-127

Author(s):

Mai Vo Quang ◽

Sang Nguyen Xuan

Keyword(s):

Graphene Oxide ◽

Diffuse Reflectance ◽

Solar Irradiation ◽

Zno Nanorod ◽

X Ray Diffraction ◽

Facile Hydrothermal Method ◽

Photocatalytic Ability ◽

Visible Light Absorption ◽

X Ray

In this work, nanohybridization of ZnO nanorod and graphene oxide (GO) were prepared by a facile hydrothermal method. The effects of GO on crystal structure and surface morphology of ZnO were revealed by Scanning electron microscopy (SEM), Raman, and X-ray diffraction (XRD). The presence of GO in the composite resulted the ZnO nanorod more uniform which its diameter size was decreased. Optical properties characterized by UV-vis diffuse reflectance spectra (DRS) showed that the ZnO/GO composite has the narrower bandgap value and the better visible-light absorption characterisitics in compare to the bare ZnO. As a result, the photocatalytic ability in degradation of methylene blue under solar irradiation was enhanced in the ZnO/GO composite.

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In Situ Synchrotron X-Ray Diffraction Characterization of the Synthesis of Graphene Oxide and Reduced Graphene Oxide

ECS Meeting Abstracts ◽

10.1149/ma2015-02/10/606 ◽

2015 ◽

Keyword(s):

Graphene Oxide ◽

Reduced Graphene Oxide ◽

X Ray Diffraction ◽

X Ray ◽

Reduced Graphene

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Hydrogen Interaction with Defects in Nanocrystalline, Polycrystalline and Epitaxial Pd Films

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.26.123 ◽

2013 ◽

Vol 26 ◽

pp. 123-133 ◽

Cited By ~ 3

Author(s):

Jakub Čížek ◽

Oksana Melikhova ◽

Marián Vlček ◽

František Lukáč ◽

Martin Vlach ◽

...

Keyword(s):

Acoustic Emission ◽

Structural Changes ◽

High Stress ◽

Positron Annihilation Spectroscopy ◽

Structural Development ◽

Misfit Dislocations ◽

X Ray Diffraction ◽

X Ray ◽

Hydrogen Interaction

Hydrogen interaction with defects and structural development of Pd films with various microstructures were investigated. Nanocrystalline, polycrystalline and epitaxial Pd films were prepared and electrochemically loaded with hydrogen. Structural changes of Pd films caused by absorbed hydrogen were studied by in-situ X-ray diffraction combined with acoustic emission and measurement of electromotorical force. Development of defects during hydrogen loading was investigated by positron annihilation spectroscopy. It was found that hydrogen firstly fills open volume defects existing already in the films and subsequently it occupies also interstitial sites in Pd lattice. Absorbed hydrogen causes volume expansion, which is strongly anisotropic in thin films. This introduces high stress into the films loaded with hydrogen. Acoustic emission measurements revealed that when hydrogen-induced stress achieves a certain critical level rearrangement of misfit dislocations takes place. The stress which grows with increasing hydrogen concentration can be further released by plastic deformation and also by detachment of the film from the substrate.

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Evidence of Ion-Beam-Induced Annealing in Graphene Oxide Films Using in Situ X-Ray Diffraction and Spectroscopy Techniques

The Journal of Physical Chemistry C ◽

10.1021/acs.jpcc.7b10699 ◽

2018 ◽

Vol 122 (17) ◽

pp. 9632-9640 ◽

Cited By ~ 8

Author(s):

Chetna Tyagi ◽

S. A. Khan ◽

Indra Sulania ◽

R. Meena ◽

D. K. Avasthi ◽

...

Keyword(s):

Graphene Oxide ◽

Ion Beam ◽

Oxide Films ◽

X Ray Diffraction ◽

X Ray

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The Use of Advanced Analytical Techniques for Characterization of the Chemical, Physical, and Crystallographic Nature of a Surface

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100071107 ◽

1973 ◽

Vol 31 ◽

pp. 132-133 ◽

Cited By ~ 1

Author(s):

R. E. Herfert

Keyword(s):

Surface Characterization ◽

Analytical Techniques ◽

X Ray Diffraction ◽

Depth Of Penetration ◽

X Ray ◽

The Past ◽

Transmission Electron ◽

Scanning Electron

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.

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