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

2018 ◽  
Vol 122 (17) ◽  
pp. 9632-9640 ◽  
Author(s):  
Chetna Tyagi ◽  
S. A. Khan ◽  
Indra Sulania ◽  
R. Meena ◽  
D. K. Avasthi ◽  
...  
2016 ◽  
Vol 120 (27) ◽  
pp. 14984-14990 ◽  
Author(s):  
Qin Pan ◽  
Ching-Chang Chung ◽  
Nanfei He ◽  
Jacob L. Jones ◽  
Wei Gao

2014 ◽  
Vol 904 ◽  
pp. 150-154
Author(s):  
Zhe Wei Yang ◽  
Xin Fan ◽  
Li Ang Guo ◽  
Wei Ting Wei

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.


1994 ◽  
Vol 299 ◽  
Author(s):  
Gary A. Gibson ◽  
Davis A. Lange ◽  
Charles M. Falco

AbstractWe have used Molecular Beam Epitaxy (MBE) to successfully grow films that are predominantly IrSi3 on both Si(111) and Si(100) substrates by codeposition of Si and Ir in a 3:1 ratio. Bragg-Brentano and Seemann-Bohlin x-ray diffraction reveal that polycrystalline IrSi3 films form as low as 450 °C. This is the lowest temperature yet reported for growth of this iridium silicide phase. These x-ray diffraction techniques, along with Transmission Electron Microscope (TEM) diffraction and in situ Low Energy Electron Diffraction (LEED), show that at higher deposition temperatures codeposition can form IrSi3 films on Si(111) that consist predominantly of a single epitaxial growth orientation. Ion beam channeling and x-ray rocking curves show that the epitaxial quality of IrSi3 films deposited on Si(111) is superior to that of IrSi3 films deposited on Si(100). We also present evidence for several new epitaxial IrSi3 growth modes on Si(111) and Si(100).


1988 ◽  
Vol 126 ◽  
Author(s):  
John F. Knudsen ◽  
R. C. Bowman ◽  
P. M. Adams ◽  
R. Newman ◽  
J. P. Hurrell ◽  
...  

ABSTRACTEpitaxial regrowth of deposited amorphous silicon has been previously described utilizing ion implantation amorphization, ion mixing and thermal anneal. This paper evaluates the effects of these process steps on crystalline quality utilizing Rutherford Backscattering (RBS), x-ray diffraction rocking curves and Raman scattering.In situ (during implantation) regrowth results in defective crystallinity. In contrast, when there is no in situ regrowth, the post anneal crystallinity is equivalent by RBS and x-ray evaluation to virgin single crystal wafers. In situ regrowth is most pronounced during the high beam current ion mixing type implants which produce wafer temperatures of about 250°C. The final crystalline quality which results from different sequences of amorphization and ion mixing implants, is strongly dependent upon the amount of in situ regrowth which has occurred. The greater the in situ regrowth the poorer the final crystalline quality.


2021 ◽  
Vol 28 (2) ◽  
pp. 550-565 ◽  
Author(s):  
David Yang ◽  
Nicholas W. Phillips ◽  
Kay Song ◽  
Ross J. Harder ◽  
Wonsuk Cha ◽  
...  

Focused ion beam (FIB) techniques are commonly used to machine, analyse and image materials at the micro- and nanoscale. However, FIB modifies the integrity of the sample by creating defects that cause lattice distortions. Methods have been developed to reduce FIB-induced strain; however, these protocols need to be evaluated for their effectiveness. Here, non-destructive Bragg coherent X-ray diffraction imaging is used to study the in situ annealing of FIB-milled gold microcrystals. Two non-collinear reflections are simultaneously measured for two different crystals during a single annealing cycle, demonstrating the ability to reliably track the location of multiple Bragg peaks during thermal annealing. The thermal lattice expansion of each crystal is used to calculate the local temperature. This is compared with thermocouple readings, which are shown to be substantially affected by thermal resistance. To evaluate the annealing process, each reflection is analysed by considering facet area evolution, cross-correlation maps of the displacement field and binarized morphology, and average strain plots. The crystal's strain and morphology evolve with increasing temperature, which is likely to be caused by the diffusion of gallium in gold below ∼280°C and the self-diffusion of gold above ∼280°C. The majority of FIB-induced strains are removed by 380–410°C, depending on which reflection is being considered. These observations highlight the importance of measuring multiple reflections to unambiguously interpret material behaviour.


2016 ◽  
Vol 113 (40) ◽  
pp. 11088-11093 ◽  
Author(s):  
Philippe Poulin ◽  
Rouhollah Jalili ◽  
Wilfrid Neri ◽  
Frédéric Nallet ◽  
Thibaut Divoux ◽  
...  

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.


2021 ◽  
Vol 10 (1) ◽  
pp. 122-127
Author(s):  
Mai Vo Quang ◽  
Sang Nguyen Xuan

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.


2018 ◽  
Vol 173 (9-10) ◽  
pp. 740-750 ◽  
Author(s):  
L. Silipigni ◽  
M. Cutroneo ◽  
G. Salvato ◽  
L. Torrisi
Keyword(s):  
X Ray ◽  

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