Utilization of electron-beam irradiation under atomic-scale chemical mapping for evaluating the cycling performance of lithium transition metal oxide cathodes

2021 ◽  
Author(s):  
Jae-Hyun Shim ◽  
Hyosik Kang ◽  
Sanghun Lee ◽  
Young-Min Kim
Keyword(s):  
Scanning Transmission Electron Microscopy ◽  
High Performance ◽  
Lithium Ion ◽  
Cycling Performance ◽  
Atomic Scale ◽  
Chemical Mapping ◽  
X Ray ◽  
Transmission Electron ◽  
Oxide Cathodes ◽  
Scanning Transmission

With the development of high-performance lithium ion batteries, scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray spectroscopy (EDX) has been widely applied as a high-precision technique to investigate...

scholarly journals In-Depth Structural and Optical Analysis of Ce-modified ZnO Nanopowders with Enhanced Photocatalytic Activity Prepared by Microwave-Assisted Hydrothermal Method

Catalysts ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 551 ◽  
Author(s):  
Otman Bazta ◽  
Ana Urbieta ◽  
Susana Trasobares ◽  
Javier Piqueras ◽  
Paloma Fernández ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Photocatalytic Activity ◽  
Scanning Transmission Electron Microscopy ◽  
Atomic Scale ◽  
X Ray ◽  
Microwave Assisted ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission

Pure and Ce-modified ZnO nanosheet-like polycrystalline samples were successfully synthesized by a simple and fast microwave-based process and tested as photocatalytic materials in environmental remediation processes. In an attempt to clarify the actual relationships between functionality and atomic scale structure, an in-depth characterization study of these materials using a battery of complementary techniques was performed. X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HRTEM), high-angle annular dark field-scanning transmission electron microscopy (HAADF-STEM), energy-dispersive X-Ray spectroscopy-scanning transmission electron microscopy (STEM-XEDS), photoluminescence spectroscopy (PL) and UV–Visible absorption spectroscopy were used to evaluate the effect of Ce ions on the structural, morphological, optical and photocatalytic properties of the prepared ZnO nanostructures. The XRD results showed that the obtained photocatalysts were composed of hexagonal, wurtzite type crystallites in the 34–44 nm size range. The SEM and TEM showed nanosheet-shaped crystallites, a significant fraction of them in contact with bundles of randomly oriented and much smaller nanoparticles of a mixed cerium–zinc phase with a composition close to Ce0.68Zn0.32Ox. Importantly, in clear contrast to the prevailing proposals regarding this type of materials, the STEM-XEDS characterization of the photocatalyst samples revealed that Ce did not incorporate into the ZnO crystal lattice as a dopant but that a heterojunction formed between the ZnO nanosheets and the Ce–Zn mixed oxide phase nanoparticles instead. These two relevant compositional features could in fact be established thanks to the particular morphology obtained by the use of the microwave-assisted hydrothermal synthesis. The optical study revealed that in the ZnO:Ce samples optical band gap was found to decrease to 3.17 eV in the samples with the highest Ce content. It was also found that the ZnO:Ce (2 at.%) sample exhibited the highest photocatalytic activity for the degradation of methylene blue (MB), when compared to both the pure ZnO and commercial TiO2-P25 under simulated sunlight irradiation. The kinetics of MB photodegradation in the presence of the different photocatalysts could be properly described using a Langmuir–Hinshelwood (LH) model, for which the ZnO:Ce (2 at.%) sample exhibited the highest value of effective kinetic constant.

scholarly journals Local crystallographic shear structures in a[201] extended mixed dislocations of SrTiO3 unraveled by atomic-scale imaging using transmission electron microscopy and spectroscopy

2019 ◽  
Vol 213 ◽  
pp. 245-258 ◽  
Author(s):  
Hongchu Du ◽  
Chun-Lin Jia ◽  
Joachim Mayer
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
Atomic Scale ◽  
X Ray ◽  
Shear Structures ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Crystallographic Shear ◽  
Electron Energy Loss

Atomic details of extended mixed dislocations in a SrTiO3 bicrystal are studied using scanning transmission electron microscopy, electron energy loss spectroscopy, and energy dispersive X-ray spectroscopy techniques.

Combined Analytical Techniques for the ELMISKOP 101 and 102

1974 ◽  
Vol 32 ◽  
pp. 418-419
Author(s):  
H.M. Thieringer ◽  
C. Weichan
Keyword(s):  
Electron Microscopy ◽  
Scanning Transmission Electron Microscopy ◽  
High Performance ◽  
Analytical Techniques ◽  
Secondary Electrons ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Electron Microscopes ◽  
Scanning Electron

The high performance transmission electron microscopes ELMISKOP 101 and 102 are increasingly used in the analytical field. This is especially favoured by the fact that five different analysis and imaging modes can be adopted by optional accessories: for wavelength dispersive X-ray microanalysis, energy dispersive X-ray microanalysis, scanning transmission electron microscopy (STEM), scanning electron microscopy (SEM) by secondary electrons, and image current measurement.

scholarly journals Chemical Quantification of Atomic-Scale EDS Maps under Thin Specimen Conditions

2014 ◽  
Vol 20 (6) ◽  
pp. 1782-1790 ◽  
Author(s):  
Ping Lu ◽  
Eric Romero ◽  
Shinbuhm Lee ◽  
Judith L. MacManus-Driscoll ◽  
Quanxi Jia
Keyword(s):  
Atomic Scale ◽  
Specimen Thickness ◽  
Peak Width ◽  
Thin Specimen ◽  
Gaussian Peak ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
The Relationship ◽  
Chemical Quantification

AbstractWe report our effort to quantify atomic-scale chemical maps obtained by collecting energy-dispersive X-ray spectra (EDS) using scanning transmission electron microscopy (STEM) (STEM-EDS). With thin specimen conditions and localized EDS scattering potential, the X-ray counts from atomic columns can be properly counted by fitting Gaussian peaks at the atomic columns, and can then be used for site-by-site chemical quantification. The effects of specimen thickness and X-ray energy on the Gaussian peak width are investigated using SrTiO3 (STO) as a model specimen. The relationship between the peak width and spatial resolution of an EDS map is also studied. Furthermore, the method developed by this work is applied to study cation occupancy in a Sm-doped STO thin film and antiphase boundaries (APBs) present within the STO film. We find that Sm atoms occupy both Sr and Ti sites but preferably the Sr sites, and Sm atoms are relatively depleted at the APBs likely owing to the effect of strain.

scholarly journals FEI Tecnai G2 F20

2016 ◽  
Vol 2 ◽  
Author(s):  
Martina Luysberg ◽  
Marc Heggen ◽  
Karsten Tillmann
Keyword(s):  
Scanning Transmission Electron Microscopy ◽  
Dark Field ◽  
Conventional Imaging ◽  
Electron Loss ◽  
High Angle ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Set Up ◽  
Elemental Maps

The FEI Titan Tecnai G2 F20 is a versatile transmission electron microscope which is equipped with a Gatan Tridiem 863P post column image filter (GIF) and a high angle energy dispersive X-ray (EDX) detector. This set up allows for a variety of experiments such as conventional imaging and diffraction, recording of bright- and dark-field scanning transmission electron microscopy (STEM) images, or acquiring elemental maps extracted from energy electron loss spectra (EELS) or EDX signals.

scholarly journals Atomic-Scale Analysis of Chemical Bonding of Delaminated Graphene at Faceted SiC by Aberration-Corrected Scanning Transmission Electron Microscopy

2013 ◽  
Vol 19 (S2) ◽  
pp. 1238-1239
Author(s):  
G. Nicotra ◽  
Q.M. Ramasse ◽  
I. Deretzis ◽  
C. Bongiorno ◽  
C. Spinella ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chemical Bonding ◽  
Scanning Transmission Electron Microscopy ◽  
Atomic Scale ◽  
Scale Analysis ◽  
Scanning Transmission Electron ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Aberration Corrected

Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.

Sign in / Sign up

Export Citation Format

Share Document