Coupling In Situ TEM and Ex Situ Analysis to Understand Heterogeneous Sodiation of Antimony

Carbon nanotubes (NTs) have novel electronic properties and exceptionally high Young's moduli on the order of TPa. so NTs have potential applications in advanced composite materials such as conductive polymers, electromagnetic-radio frequency interference (EMI/RFI) shielding material and opto-electronic materials. The utility of the nanotubes in composite applications depends strongly on the ability to disperse the NTs homogeneously throughout the matrix without destroying the integrity of the NTs. Furthermore, interfacial bonding between the NT and matrix is necessary to achieve load transfer across the interface, which is desirable for improving the mechanical properties of polymer composites.In this work, aligned multiwalled carbon nanotubes (MWNTs) produced by continuous chemical vapor deposition (CVD) (see Fig.l), were homogeneously dispersed in polystyrene (PS) matrices by a simple solution-evaporation method. Using this procedure, we made uniform MWNT-PS composite films ∼0.4mm thick for ex-situ mechanical tensile test and very thin films, ∼100nm, for in-situ TEM tests, as shown in Fig.2.

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In-situ TEM studies on stick-slip friction characters of sp2 nanocrystallited carbon films

Friction ◽

10.1007/s40544-021-0551-z ◽

2022 ◽

Author(s):

Xue Fan ◽

Zelong Hu ◽

Wenchao Huang

Keyword(s):

Shear Stress ◽

Shear Strength ◽

Interfacial Adhesion ◽

Carbon Films ◽

Ex Situ ◽

In Situ Tem ◽

Stick Slip ◽

Slip Step ◽

Transmission Electron

AbstractCarbon films with two different kinds of sp2 nanocrystallited structure were investigated to study the stick-slip friction with the in-situ and ex-situ tests. In-situ transmission electron microscope (TEM) observation and nanofriction tests revealed that the origins of stick and slip varied with shear stress and film deformation. At the stick stage, shear stress gradually increased with the contact strengthened until reached the shear strength to break the interfacial adhesion; at the slip stage, the shear stress decreased and accompanied with film deformation. During the sliding process, adhesive deformation resulted in the large stick-slip step while ploughing deformation led to a smoother step. Ex-situ nanofriction tests on a series of sp2 nanocrystallited carbon films with different irradiation energies showed the expected sliding behavior with the in-situ results. This study first clarified the mechanism of stick-slip friction with the in-situ TEM observation, which plays the important role for the micro and nano application of sp2 nanocrystallited carbon films.

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Ex situ and In situ TEM study of the relaxation of thin films by the modified frank-read mechanism

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100131346 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1342-1343

Author(s):

F.K. LeGoues

Keyword(s):

Thin Films ◽

Strain Relaxation ◽

Lattice Parameter ◽

Buffer Layers ◽

Ex Situ ◽

In Situ Tem ◽

Wide Range ◽

Strong Resemblance ◽

Image Position

In recent papers, we have described a novel mechanism for strain relaxation of thin films. Because of its strong resemblance to the well known Frank-Read sources of dislocations, it was called the “Modified-Frank-Read” (MFR) mechanism. This process was first observed during the growth of compositionally graded SiGe/Si(001) thin films, where it results in dislocations pile-ups being injected deep into an initially perfect substrate, leaving the topmost part of the film relaxed and nominally defect free. This last observation opens the door to a wide range of electronic applications since it makes it possible to grow electronic grade buffer layers of arbitrary composition and lattice parameter.The exact mechanism of the reproduction of dislocations was identified through tilting experiment and analysis of several compositionally graded SiGe/Si(001) structures. These also provided the important parameters controlling this mode of strain relaxation. We thus demonstrated that the MFR mechanism corresponds to the multiplication of “corner dislocations” (dislocations whose line forms a 90° angle) by simultaneous glide on two (111) planes.

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On the Mechanism of Resistive Switching in MIM Capacitors – An Approach with In-situ TEM Experiments

MRS Proceedings ◽

10.1557/proc-0907-mm06-02 ◽

2005 ◽

Vol 907 ◽

Cited By ~ 1

Author(s):

Herbert Schroeder

Keyword(s):

Resistive Switching ◽

High Vacuum ◽

Film Structure ◽

Ex Situ ◽

In Situ Tem ◽

Ion Milling ◽

Window Technique ◽

Set Up ◽

Mim Capacitors

AbstractIn this contribution an in-situ TEM experiment is suggested to observe the microstructure of a metal/oxide insulator/metal (MIM) capacitor structure during resistive switching due to an applied external voltage or current. The motivation for such an experiment is the fact that there is a large pool on the resistive switching data in the literature, but there is no agreement on the mechanism, which in part is due to missing microstructural observations of the effects. For such an experiment a special TEM sample holder has been developed allowing controlled in-situ application of temperature (RT to 300°C) with a heating stage and of voltage (current) as a part of a 4-terminal resistance measurement set-up. This is combined with a special TEM sample preparation method, the “window”-technique, so that no thinning of the MIM thin film structure is necessary at all (which is an advantage as the oxides are known to be very sensitive to damage introduced by methods such as ion-milling). Special electrode configurations have been designed to allow nearly undisturbed TEM observation of the switching insulator. Identical samples will also be investigated ex-situ in conventional switching experiments to identify the influence of the special TEM environment (high vacuum, irradiation with energetic electrons).

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Influence of annealing temperature on the properties of TiO2 films annealed by ex situ and in situ TEM

Journal of Wuhan University of Technology-Mater Sci Ed ◽

10.1007/s11595-012-0591-3 ◽

2012 ◽

Vol 27 (6) ◽

pp. 1014-1019 ◽

Cited By ~ 4

Author(s):

Tangchao Peng ◽

Xiangheng Xiao ◽

Feng Ren ◽

Jinxia Xu ◽

Xiaodong Zhou ◽

...

Keyword(s):

Annealing Temperature ◽

Ex Situ ◽

In Situ Tem ◽

Tio2 Films

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Direct Observation of Single Displacement Cascade in Pyrochlore by Tv-Rate In-Situ TEM and Ex-Situ HRTEM

Microscopy and Microanalysis ◽

10.1017/s1431927600028117 ◽

2001 ◽

Vol 7 (S2) ◽

pp. 408-409

Author(s):

J. Lian ◽

L. M. Wang ◽

S. X. Wang ◽

R. C. Ewing

Keyword(s):

Ion Irradiation ◽

Heavy Ion ◽

Ex Situ ◽

In Situ Tem ◽

Direct Impact ◽

Displacement Cascade ◽

Amorphous Domain ◽

Rapid Kinetics ◽

Kinetics Of

The ion irradiation-induced crystalline-to-amorphous transformation has been studied in many complex ceramics. Direct impact amorphization has been considered to be one of the fundamental amorphization mechanisms for complex ceramics under heavy ion irradiation . Based on the directimpact model, a highly energetic incident ion transfers its kinetic energy to the target as a thermal spike within 10“13 sec creating a “molten-like” displacement cascade, typically nanometer-scaled in diameter (as indicated by the result of a computer simulation in Fig. 1). This “molten” zone quickly quenches to a small amorphous domain within a few pico-seconds. Epitaxial recrystallization occurs around the amorphous/crystalline interface, so that the size of amorphous domains decrease with time. The accumulation and overlap of small amorphous domains eventually leads to complete amorphization of the irradiated material. Although the in-situTEM technique with the setup shown in Fig. 2 has been extensively applied to the study of the amorphization process in complex ceramics, most of the previous studies relied on in-situobservation of the electron diffraction pattern, and there has been a lack of solid evidence of direct impact amorphization due to the small nature of the cascades and the rapid kinetics of its evolution.

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In Situ TEM Study of Rh Particle Sintering for Three-Way Catalysts in High Temperatures

Catalysts ◽

10.3390/catal11010019 ◽

2020 ◽

Vol 11 (1) ◽

pp. 19

Author(s):

Hiroki Nakayama ◽

Makoto Nagata ◽

Hideki Abe ◽

Yukihiro Shimizu

Keyword(s):

Density Functional ◽

Platinum Group Metals ◽

Ex Situ ◽

In Situ Tem ◽

Support Material ◽

Functional Theory ◽

N2 Atmosphere ◽

Vacuum Atmosphere ◽

Heating Up

One of the main factors in the deterioration of automobile three-way catalysts is the sintering of platinum group metals (PGMs). In this study, we used in situ tunneling electron microscopy (TEM) to examine the sintering of Rh particles as the temperature increases. Two types of environmental conditions were tested, namely, vacuum atmosphere with heating up to 1050 °C, and N2 with/without 1% O2 at 1 atm and up to 1000 °C. Under vacuum, Rh particles appeared to be immersed in ZrO2. In contrast, at 1 atm N2 with or without 1% O2, the sintered Rh particles appeared spherical and not immersed in ZrO2. The latter trend of Rh sintering resembles the actual engine-aged catalyst observed ex situ in this study. In the N2 atmosphere, the sintering of support material (ZrO2 or Y-ZrO2) was first observed by in situ TEM, followed by Rh particle sintering. The Rh particle size was slightly smaller on Y-ZrO2 compared to that on ZrO2. To better understand these experimental results, density functional theory was used to calculate the systems’ junction energies, assuming three layers of Rh(111) 4 × 4 structures joined to the support material (ZrO2 and Y-ZrO2). The calculated energies were consistent with the in situ TEM observations in the N2 atmosphere.

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A new deformation mechanism in Olivine? Ex-situ and in-situ TEM studies

10.22443/rms.emc2020.673 ◽

2021 ◽

Author(s):

Dominique Schryvers ◽

Keyword(s):

Deformation Mechanism ◽

Ex Situ ◽

In Situ Tem

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In-Situ Transmission Electron Microscopy of the Solid-Phase Epitaxial Growth of GaAs: Sample Preparation and Artifact Characterization

MRS Proceedings ◽

10.1557/proc-480-257 ◽

1997 ◽

Vol 480 ◽

Cited By ~ 1

Author(s):

K. B. Belay ◽

M. C. Ridgway ◽

D. J. Llewellyn

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Sample Preparation ◽

Epitaxial Growth ◽

Solid Phase ◽

Ion Beam ◽

Ex Situ ◽

In Situ Tem ◽

Transmission Electron

AbstractIn-situ transmission electron microscopy (TEM) has been used to characterize the solidphase epitaxial growth of amorphized GaAs at a temperature of 260°C. To maximize heat transfer from the heated holder to the sample and minimize electron-irradiation induced artifacts, non-conventional methodologies were utilized for the preparation of cross-sectional samples. GaAs (3xI) mm rectangular slabs were cut then glued face-to-face to a size of (6x3) mm stack by maintaining the TEM region at the center. This stack was subsequently polished to a thickness of ~ 200 ýtm. A 3 mm disc was then cut from it using a Gatan ultrasonic cutter. The disc was polished and dimpled on both sides to a thickness of ~15 mimT.h is was ion-beam milled at liquid nitrogen temperature to an electron-transparent layer. From a comparison of in-situ and ex-situ measurements of the recrystallization rate, the actual sample temperature during in-situ characterization was estimated to deviate by ≤ 20°C from that of the heated holder. The influence of electron-irradiated was found to be negligible by comparing the recrystallization rate and microstructure of irradiated and unirradiated regions of comparable thickness. Similarly, the influence of “thin-foil effect” was found to be negligible by comparing the recrystallization rate and microstructure of thick and thin regions, the former determined after the removal of the sample from the microscope and further ion-beam milling of tens of microns of material. In conclusion, the potential influence of artifacts during in-situ TEM can be eliminated by the appropriate choice of sample preparation procedures.

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In Situ TEM Heating Study of the γ Lamellae Formation inside the α2 Matrix of a Ti-45Al-7.5Nb Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.146-147.1365 ◽

2010 ◽

Vol 146-147 ◽

pp. 1365-1368 ◽

Cited By ~ 1

Author(s):

Li Mei Cha ◽

Helmut Clemens ◽

Gerhard Dehm ◽

Zao Li Zhang

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Ex Situ ◽

In Situ Tem ◽

Transmission Electron ◽

Initial Stage ◽

Heat Treated ◽

The Matrix ◽

In Situ Heating

In-situ heating transmission electron microscopy (TEM) was employed to investigate the initial stage of lamellae formation in a high Nb containing γ-TiAl based alloy. A Ti-45Al-7.5Nb alloy (at %), which was heat treated and quenched in a non-equilibrium state such that the matrix consists of ordered a2 grains, was annealed inside a TEM up to 750 °C. The in-situ TEM study reveals that g laths precipitate in the a2 matrix at ~ 750 °C possessing the classical Blackburn orientation relationship, i.e. (0001)a2 // (111)g and [11-20]a2 // <110]g. The microstructure of the in-situ TEM experiment is compared to results from ex-situ heating and subsequent TEM studies.

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