Probing Structure/Property Relationships of Ce-rich Oxygen Evolution Catalysts by Advanced Transmission Electron Microscopy

Transmission electron microscopy plays an important role in the study of the influence polymerization conditions have on the morphology of structured latex particles and thus in the understanding of the morphological effect of such particles on the structure-property relationships of polymeric end products.Structured latex particles are prepared by seeded emulsion polymerization, where the first stage is a polymerization of ”the core” poly(n-butyl acrylate) (PBA), followed by a second stage polymerization of ”the shell” poly(benzyl methacrylate/styrene) (P(BM/St)) at various ratios. The changes in polymerization conditions include such variables as the polymerization mode (batch vs. semicontinuous), core/shell ratio, shell thickness, and shell composition. Morphology studies of the structured latex particles are performed by transmission electron microscopy on preferentially stained samples. In a small vial, a few drops of latex sample are combined with a few drops of uranyl acetate (UAc) 2% solution. The uranyl acetate serves as a negative staining to better delineate the particles edges.

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A Review of Grain Boundary and Heterointerface Characterization in Polycrystalline Oxides by (Scanning) Transmission Electron Microscopy

Crystals ◽

10.3390/cryst11080878 ◽

2021 ◽

Vol 11 (8) ◽

pp. 878

Author(s):

Hasti Vahidi ◽

Komal Syed ◽

Huiming Guo ◽

Xin Wang ◽

Jenna Laurice Wardini ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Experimental Studies ◽

Atomic Scale ◽

Polycrystalline Materials ◽

Structure Property ◽

Ceramic Oxides ◽

Structure Property Relationships ◽

Transmission Electron ◽

Scanning Transmission

Interfaces such as grain boundaries (GBs) and heterointerfaces (HIs) are known to play a crucial role in structure-property relationships of polycrystalline materials. While several methods have been used to characterize such interfaces, advanced transmission electron microscopy (TEM) and scanning TEM (STEM) techniques have proven to be uniquely powerful tools, enabling quantification of atomic structure, electronic structure, chemistry, order/disorder, and point defect distributions below the atomic scale. This review focuses on recent progress in characterization of polycrystalline oxide interfaces using S/TEM techniques including imaging, analytical spectroscopies such as energy dispersive X-ray spectroscopy (EDXS) and electron energy-loss spectroscopy (EELS) and scanning diffraction methods such as precession electron nano diffraction (PEND) and 4D-STEM. First, a brief introduction to interfaces, GBs, HIs, and relevant techniques is given. Then, experimental studies which directly correlate GB/HI S/TEM characterization with measured properties of polycrystalline oxides are presented to both strengthen our understanding of these interfaces, and to demonstrate the instrumental capabilities available in the S/TEM. Finally, existing challenges and future development opportunities are discussed. In summary, this article is prepared as a guide for scientists and engineers interested in learning about, and/or using advanced S/TEM techniques to characterize interfaces in polycrystalline materials, particularly ceramic oxides.

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Diffusion Characteristics of Cu in TiN Thin Films

MRS Proceedings ◽

10.1557/proc-686-a9.8 ◽

2001 ◽

Vol 686 ◽

Author(s):

Abhishek Gupta ◽

Hiyan Wang ◽

Alex V. Kvit ◽

Gerd Duscher ◽

Jay Narayan

Keyword(s):

Electron Microscopy ◽

Thin Films ◽

Transmission Electron Microscopy ◽

Diffusion Barrier ◽

Pulse Laser Deposition Technique ◽

Structure Property ◽

Contrast Imaging ◽

Transmission Electron ◽

Diffusion Characteristics ◽

Tin Thin Films

AbstractWe have investigated the diffusion characteristics of Cu in nanocrystalline, polycrystalline and single crystal TiN thin films, which are being used as a diffusion barrier for sub-quarter-micron metallization. These films were synthesized on Si (100) substrate by first ablating TiN and then ablating Cu targets using Pulse Laser Deposition technique. The three different microstructures of TiN were achieved by growing the films at different substrate temperatures, where higher temperatures (650 °C) leads to epitaxy. Then a uniform thin layer of Cu was deposited on TiN/Si substrate at room temperature for all the three depositions above. These structures were characterized using X-Ray diffraction technique and high-resolution transmission electron microscopy. Each sample is then annealed at 500 °C for 30min to study the diffusion barrier characteristics as a function of microstructure of TiN. Study of diffusion profile and Cu concentration measurement were performed using Scanning Transmission Electron Microscopy-Z contrast Imaging (0.12nm resolution), Electron Energy Loss Spectroscopy and Secondary Ion Mass Spectroscopy. From the results obtained the effect of microstructure of TiN thin films on the diffusion characteristics of Cu after annealing was analyzed. Four points probe resistivity measurements were made to establish structure property correlations.

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TEM/STEM Characterization of Rapidly Solidified Aluminum Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100117236 ◽

1985 ◽

Vol 43 ◽

pp. 30-31

Author(s):

R. J. Kar ◽

T. P. McHale ◽

R. T. Kessler

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Aluminum Alloys ◽

High Strength ◽

Advanced Materials ◽

Structure Property ◽

Aerospace Applications ◽

Transmission Electron ◽

Scanning Transmission ◽

Rapidly Solidified

Low-density and high strength-type rapidly solidified (RST) aluminum alloys offer promise for structural aerospace applications. At Northrop, as part of a continuing program to establish structure-property relationships in advanced materials, detailed transmission electron microscopy (TEM)/scanning transmission electron microscopy (STEM) of candidate RST aluminum-lithium (Al-Li) and high strength (7XXX-type) aluminum-copper-magnesium-zinc (Al-Cu-Mg-Zn) alloys is routinely performed. This paper describes typical microstructural features that we have observed in these alloys.Figure 1 illustrates the microstructure of an inert-gas atomized RST Al-Li-Cu-Mg-Zr alloy. Frequently the grain boundaries are decorated with continuous or semi-continuous stringers of oxide that are relatively opaque to the incident electron beam. These have been identified to be Al-,Mg-, and Li- containing oxides present on powder particle surfaces prior to consolidation, and which have not been adequately broken up and dispersed by post-consolidation processing. The microstructures of these alloys are generally characterized by unrecystallized grains and equiaxed sub-grains pinned by fine (0.2μm) precipitates. These have been identified to be Al3Zr dispersoids using a combination of selected area diffraction/energy-dispersive x-ray (SAD/EDX) methods.

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Possibility of an integrated transmission electron microscope: enabling complex in-situ experiments

Journal of Materials Science ◽

10.1007/s10853-020-05598-z ◽

2021 ◽

Vol 56 (9) ◽

pp. 5309-5320

Author(s):

Khalid Hattar ◽

Katherine L. Jungjohann

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Extreme Environments ◽

Structure Property ◽

Multispectral Data ◽

Transmission Electron ◽

Holistic Understanding ◽

In Situ Experiments ◽

Scanning Transmission

Abstract Multimodal in-situ experiments are the wave of the future, as this approach will permit multispectral data collection and analysis during real-time nanoscale observation. In contrast, the evolution of technique development in the electron microscopy field has generally trended toward specialization and subsequent bifurcation into more and more niche instruments, creating a challenge for reintegration and backward compatibility for in-situ experiments on state-of-the-art microscopes. We do not believe this to be a requirement in the field; therefore, we propose an adaptive instrument that is designed to allow nearly simultaneous collection of data from aberration-corrected transmission electron microscopy (TEM), probe-corrected scanning transmission electron microscopy, ultrafast TEM, and dynamic TEM with a flexible in-situ testing chamber, where the entire instrument can be modified as future technologies are developed. The value would be to obtain a holistic understanding of the underlying physics and chemistry of the process-structure–property relationships in materials exposed to controlled extreme environments. Such a tool would permit the ability to explore, in-situ, the active reaction mechanisms in a controlled manner emulating those of real-world applications with nanometer and nanosecond resolution. If such a powerful tool is developed, it has the potential to revolutionize our materials understanding of nanoscale mechanisms and transients. Graphical Abstract

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Direct Observation of Oxygen Evolution and Surface Restructuring on Mn2O3 Nanocatalysts Using In Situ and Ex Situ Transmission Electron Microscopy

Nano Letters ◽

10.1021/acs.nanolett.1c02378 ◽

2021 ◽

Author(s):

Guangming Zhao ◽

Yunduo Yao ◽

Wei Lu ◽

Guanyu Liu ◽

Xuyun Guo ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Oxygen Evolution ◽

Direct Observation ◽

Ex Situ ◽

Surface Restructuring ◽

Transmission Electron

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Interface characterization of metal matrix composites by transmission electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126342 ◽

1987 ◽

Vol 45 ◽

pp. 304-305

Author(s):

I. W. Hall ◽

A. P. Diwanji

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Metal Matrix Composites ◽

Metal Matrix ◽

Matrix Alloy ◽

Matrix Composites ◽

Structure Property ◽

Manufacturing Method ◽

Transmission Electron ◽

Structural Applications

Carbon fiber reinforced metal matrix composites (MMC's) are an attractive class of materials for automotive and aerospace structural applications because of their high strength and stiffness to weight ratios and their low coefficients of thermal expansion. Successful development of these new materials demands a thorough understanding of the structure/property/processing relationships and, in particular, a detailed understanding of the fiber/matrix interface since this region strongly influences the final mechanical properties of the system. This interface is affected by many factors including the manufacturing method, heat treatment, matrix alloy composition and wettability of the fibers but, since it is a region which is typically much less than lμm wide, it is inaccessible to direct detailed observation by any means other than transmission electron microscopy.

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