scholarly journals X-ray microscope captures nanoscale structures in 3D

MRS Bulletin ◽  
2012 ◽  
Vol 37 (6) ◽  
pp. 544-545
Keyword(s):  
X Ray ◽  
2015 ◽  
Vol 14 (03) ◽  
pp. 1550007 ◽  
Author(s):  
K. Kaviyarasu ◽  
C. Maria Magdalane ◽  
E. Manikandan ◽  
M. Jayachandran ◽  
R. Ladchumananandasivam ◽  
...  

Graphene oxide (GO) nanosheets modified with zinc oxide nanocrystals were achieved by a green wet-chemical approach. As-obtained products were characterized by XRD, Raman spectra, XPS, HR-TEM, EDS, PL and Photocatalytic studies. XRD studies indicate that the GO nanosheet have the same crystal structure found in hexagonal form of ZnO . The enhanced Raman spectrum of 2D bands confirmed formation of single layer graphene oxides. The gradual photocatalytic reduction of the GO nanosheet in the GO : ZnO suspension of ethanol was studied by using X-ray photoelectron (XPS) spectroscopy. The nanoscale structures were observed and confirmed using high resolution transmission electron microscopy (HR-TEM). The evolution of the elemental composition, especially the various numbers of layers were determined from energy dispersive X-ray spectra (EDS). PL properties of GO : ZnO nanosheet were found to be dependent on the growth condition and the resultant morphology revealed that GO nanosheet were highly transparent in the visible region. The photocatalytic performance of GO : ZnO nanocomposites was performed under UV irradiation. Therefore, the ZnO nanocrystals in the GO : ZnO composite could be applied in gradual chemical reduction and consequently tuning the electrical conductivity of the graphene oxide nanosheet.


2021 ◽  
Vol 54 (6) ◽  
Author(s):  
Hiroki Ogawa ◽  
Shunsuke Ono ◽  
Yuki Watanabe ◽  
Yukihiro Nishikawa ◽  
Shotaro Nishitsuji ◽  
...  

Small-angle X-ray scattering (SAXS) coupled with computed tomography (CT), denoted SAXS-CT, has enabled the spatial distribution of the characteristic parameters (e.g. size, shape, surface, length) of nanoscale structures inside samples to be visualized. In this work, a new scheme with Tikhonov regularization was developed to remove the effects of artifacts caused by streak scattering originating from the reflection of the incident beam in the contour regions of the sample. The noise due to streak scattering was successfully removed from the sinogram image and hence the CT image could be reconstructed free from artifacts in the contour regions.


2012 ◽  
Vol 476-478 ◽  
pp. 475-479 ◽  
Author(s):  
Yong Jun Jiang

By means of the reactive magnetron sputtering method, a series of Nb–Si–N composite films with different Si contents were deposited in an Ar, N2 and SiH4 mixture atmosphere. These films’ chemical composition, phase formation, microstructure and mechanical properties were characterized by the energy dispersive spectroscopy, X-ray diffraction, transmission electron microcopy, atomic force microscopy and nanoindentation. In the Nb–Si–N films, 3 distinct concentration regions have been observed depending on the Si content. Based on the three concentration regions, a three-step model is proposed for the film formation of the Nb–Si–N thin films. This model correlates nanoscale structures with macroscopic properties of the films.


2011 ◽  
Vol 18 (4) ◽  
pp. 580-594 ◽  
Author(s):  
O. Ponomarenko ◽  
A. Y. Nikulin ◽  
H. O. Moser ◽  
P. Yang ◽  
O. Sakata

Coherent X-ray diffraction techniques play an increasingly significant role in the imaging of nanoscale structures, ranging from metallic and semiconductor to biological objects. In material science, X-rays are usually considered to be of a low-destructive nature, but under certain conditions they can cause significant radiation damage and heat loading on the samples. The qualitative literature data concerning the tolerance of nanostructured samples to synchrotron radiation in coherent diffraction imaging experiments are scarce. In this work the experimental evidence of a complete destruction of polymer and gold nanosamples by the synchrotron beam is reported in the case of imaging at 1–10 nm spatial resolution. Numerical simulations based on a heat-transfer model demonstrate the high sensitivity of temperature distribution in samples to macroscopic experimental parameters such as the conduction properties of materials, radiation heat transfer and convection. However, for realistic experimental conditions the calculated rates of temperature rise alone cannot explain the melting transitions observed in the nanosamples. Comparison of these results with the literature data allows a specific scenario of the sample destruction in each particular case to be presented, and a strategy for damage reduction to be proposed.


RSC Advances ◽  
2014 ◽  
Vol 4 (18) ◽  
pp. 9152 ◽  
Author(s):  
Peter Sandegaard Skyt ◽  
Grethe Vestergaard Jensen ◽  
Isak Wahlstedt ◽  
Jørgen Breede Baltzer Petersen ◽  
Ludvig Paul Muren ◽  
...  

2020 ◽  
Vol 15 (1) ◽  
pp. 1-6
Author(s):  
Michel Oliveira da Silva Dantas ◽  
Denise Criado ◽  
Alejandro Zuniga ◽  
Wellington Silva ◽  
Elisabete Galeazzo ◽  
...  

Nanostructured zinc oxide (ZnO) has attracted considerable interest for a wide range of applications, including its use as an active layer in gas sensor devices and as promising emitters for field emission devices. Although it is interesting for FE purposes, the synthesis of this material can be complex and non-compatible with microelectronic processes. To overcome this issue, this paper explores ZnO nanowires growth through thermal oxidation of zinc thin films. We applied this IC-compatible procedure to fabricate field emission cathodes. Analyses of Raman spectroscopy, X‑ray photoelectron spectrometry, X‑ray diffractometry and scanning electron microscopy confirmed that the processes applied were well succeeded in obtaining nanoscale structures of ZnO with dimensions up to 4 micrometers in length and 30‑100 nanometers in diameter. Electrical characterization showed an intense electron field emission on the active area of the device, with a low turn-on electric field (2.4 volts/micrometer). An innovative system based on image processing allowed electrical current mapping throughout the active area of the devices, providing information about the uniformity of the emitted current. These results demonstrate that the low-complex fabrication procedures adopted as well as the ZnO nanomaterial itself are suitable for FE devices development.


2015 ◽  
Vol 6 ◽  
pp. 595-604 ◽  
Author(s):  
Peter Guttmann ◽  
Carla Bittencourt

Today, in material science nanoscale structures are becoming more and more important. Not only for the further miniaturization of semiconductor devices like carbon nanotube based transistors, but also for newly developed efficient energy storage devices, gas sensors or catalytic systems nanoscale and functionalized materials have to be analysed. Therefore, analytical tools like near-edge X-ray absorption fine structure (NEXAFS) spectroscopy has to be applied on single nanostructures. Scanning transmission X-ray microscopes (STXM) as well as full-field transmission X-ray microscopes (TXM) allow the required spatial resolution to study individual nanostructures. In the soft X-ray energy range only STXM was used so far for NEXAFS studies. Due to its unique setup, the TXM operated by the Helmholtz-Zentrum Berlin (HZB) at the electron storage ring BESSY II is the first one in the soft X-ray range which can be used for NEXAFS spectroscopy studies which will be shown in this review. Here we will give an overview of the different microscopes used for NEXAFS studies and describe their advantages and disadvantages for different samples.


2020 ◽  
Vol 27 (2) ◽  
pp. 386-395 ◽  
Author(s):  
K. V. Nikolaev ◽  
V. Soltwisch ◽  
P. Hönicke ◽  
F. Scholze ◽  
J. de la Rie ◽  
...  

Following the recent demonstration of grazing-incidence X-ray fluorescence (GIXRF)-based characterization of the 3D atomic distribution of different elements and dimensional parameters of periodic nanoscale structures, this work presents a new computational scheme for the simulation of the angular-dependent fluorescence intensities from such periodic 2D and 3D nanoscale structures. The computational scheme is based on the dynamical diffraction theory in many-beam approximation, which allows a semi-analytical solution to the Sherman equation to be derived in a linear-algebraic form. The computational scheme has been used to analyze recently published GIXRF data measured on 2D Si3N4 lamellar gratings, as well as on periodically structured 3D Cr nanopillars. Both the dimensional and structural parameters of these nanostructures have been reconstructed by fitting numerical simulations to the experimental GIXRF data. Obtained results show good agreement with nominal parameters used in the manufacturing of the structures, as well as with reconstructed parameters based on the previously published finite-element-method simulations, in the case of the Si3N4 grating.


2020 ◽  
Vol 11 (3-2020) ◽  
pp. 185-189
Author(s):  
K. V. Stepanova ◽  
◽  
A. M. Shulga ◽  
N. M. Yakovleva ◽  
A. N. Kokatev ◽  
...  

For the first time it was shown how to obtain microcone-shaped TiO2structures by means of anodizing of porous powder materials made of titanium sponge. It was established that during anodizing in 10 %Н2SO4+ 0,15 % HF electrolyte along with the growth of the X-ray amorphous nanoporous TiO2film a set of microcones with anatase crystalline structure is formed on the surface of titanium sponge powder particles. Microcones (height is up to 7m, base diameter is up to 5m) consist of multilayer nanoscale structures. Such structures are promising for the manufacture of new nanomaterials for catalytic and sensor devices.


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