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In situ transmission electron microscope (TEM) characterization techniques provide valuable information on structure–property correlations to understand the behavior of materials at the nanoscale. However, understanding nanoscale structures and their interaction with the electron beam is pivotal for the reliable interpretation of in situ/ex situ TEM studies. Here, we report that oxides commonly used in nanoelectronic applications, such as transistor gate oxides or memristive devices, are prone to electron beam induced damage that causes small structural changes even under very low dose conditions, eventually changing their electrical properties as examined via in situ measurements. In this work, silicon, titanium, and niobium oxide thin films are used for in situ TEM electrical characterization studies. The electron beam induced reduction of the oxides turns these insulators into conductors. The conductivity change is reversible by exposure to air, supporting the idea of electron beam reduction of oxides as primary damage mechanism. Through these measurements we propose a limit for the critical dose to be considered for in situ scanning electron microscopy and TEM characterization studies.

Liquid‐Phase Transmission Electron Microscopy (LP‐TEM) enables in situ observations of the dynamic behavior of materials in liquids at high spatial and temporal resolution. During LP‐TEM, incident electrons decompose water molecules into highly reactive species. Consequently, the chemistry of the irradiated aqueous solution is strongly altered, impacting the reactions to be observed. However, the short lifetime of these reactive species prevent their direct study. Here, the morphological changes of goethite during its dissolution are used as a marker system to evaluate the influence of radiation on the changes in solution chemistry. At low electron flux density, the morphological changes are equivalent to those observed under bulk acidic conditions, but the rate of dissolution is higher. On the contrary, at higher electron fluxes, the morphological evolution does not correspond to a unique acidic dissolution process. Combined with kinetic simulations of the steady state concentrations of generated reactive species in the aqueous medium, the results provide a unique insight into the redox and acidity interplay during radiation induced chemical changes in LP‐TEM. The results not only reveal beam‐induced radiation chemistry via a nanoparticle indicator, but also open up new perspectives in the study of the dissolution process in industrial or natural settings. In situ Liquid‐Phase Transmission Electron Microscopy observations of the morphological changes of goethite nanoparticles during its dissolution are used to evaluate the influence of radiation on changes in solution chemistry. The results not only reveal beam‐induced radiation chemistry via a nanoparticulate indicator, but also open up new perspectives in the study of dissolution processes in industrial and natural settings.

Identifying corrosion initiation events in metals and alloys demands techniques that can provide temporal and spatial resolution simultaneously. Transmission electron microscopy (TEM) enables one to obtain microstructural and chemical descriptors of materials at atomic/nanoscopic level and has been used in corrosion studies of many metal-electrolyte combinations. Conventionally, ex situ and quasi in situ TEM studies of pre- and post-corroded samples were performed, but possible experimental artifacts such as dehydrated surfaces might not fully represent the real interfacial conditions as compared to those when actually immersed in the electrolyte. Recent advances in liquid cell transmission electron microscopy (LC-TEM) allows for in situ monitoring morphological and even compositional evolutions in materials resulting from interaction with gas or liquid environments. Corrosion science, as a challenging field of research, can benefit from this unparalleled opportunity to investigate many complicated corroding systems in aqueous environments at high resolution. However, “real life” corrosion with LC-TEM is still not straightforward in implementation and there are limitations and challenging experimental considerations for conducting reliable examinations. Thus, this study has been devoted to discussing the challenges of in situ LC-TEM wherein state-of-the-art achievements in the field of relevance are reviewed.

A machining tool plays a crucial role in determining the quality of products produced through cutting or abrasive machining. The tool must have exceptional thermal and mechanical properties to produce acceptable results. The tungsten carbide with cobalt binder is a well-regarded composite material commonly used in machining tools due to its ability to meet these requirements. Research has been conducted to improve the performance of these tools, and one method is the electron beam (e-beam) treatment, which enhances the tool’s strength by exposing it to a high-energy beam. Experimental methods are often used to understand the phase transformation in alloys, but the evolution of nanoscale polycrystalline structures is yet to be fully explored. Thus, we employ molecular dynamics simulations to investigate the effect of e-beam irradiation by calculating the mechanical properties of cobalt, tungsten carbide, and tungsten carbide with cobalt binder nanocrystalline structures after undergoing e-beam irradiation treatment at different temperatures and elongation conditions. This study starts to verify the potential model by comparing melting points with experiments. Then, indentation simulations are introduced to demonstrate the relationship between normalized hardness and recovery index systematically on a free surface. Finally, the study provides qualitative observations of three different WC-Co polycrystalline structures to highlight the effect of nanosized grain distributions. Both indentation and tensile simulations analyze the structural instability based on the averaged local. This research sheds light on the underlying physics of thermal and e-beam treatments on mono and polycrystalline nanostructures.

Cryogenic transmission electron microscopy (cryo‐TEM) has impacted biology and materials science profoundly due to its power in studying aqueous specimens. However, it remains challenging to extend this technique to organic solvent systems as organic solvents are often difficult to vitrify and are unstable under electron beams. Here, we studied the response of the 23 most commonly used organic solvents to vitrification and electron exposure in cryo‐TEM experiments. Optimized vitrification method was determined for each of the solvents, and the electron tolerances of the solvents were thoroughly measured using high‐resolution imaging. Generic rules underlying the different performances of the solvents were discussed. Based on the rules, methods were developed to enhance the electron exposure stability of the organic solvents. Our results provide guidance for optimizing cryo‐TEM experiments on organic solvent specimens. To better perform cryo‐TEM experiments on organic solvent systems, this work studied the response of 23 common organic solvents to vitrification and electron exposure, listed optimized sample preparation conditions, and developed methods to enhance the electron tolerance of the samples.

The thermally-induced crystallization of anodically grown TiO2 amorphous nanotubes has been studied so far under ambient pressure conditions by techniques such as differential scanning calorimetry and in situ X-ray diffraction, then looking at the overall response of several thousands of nanotubes in a carpet arrangement. Here we report a study of this phenomenon based on an in situ transmission electron microscopy approach that uses a twofold strategy. First, a group of some tens of TiO2 amorphous nanotubes was heated looking at their electron diffraction pattern change versus temperature, in order to determine both the initial temperature of crystallization and the corresponding crystalline phases. Second, the experiment was repeated on groups of few nanotubes, imaging their structural evolution in the direct space by spherical aberration-corrected high resolution transmission electron microscopy. These studies showed that, differently from what happens under ambient pressure conditions, under the microscope’s high vacuum (p < 10−5 Pa) the crystallization of TiO2 amorphous nanotubes starts from local small seeds of rutile and brookite, which then grow up with the increasing temperature. Besides, the crystallization started at different temperatures, namely 450 and 380 °C, when the in situ heating was performed irradiating the sample with electron beam energy of 120 or 300 keV, respectively. This difference is due to atomic knock-on effects induced by the electron beam with diverse energy.

Some clinical situations in radiotherapy require electron beams to be incident on curved patient surfaces. This study presents central‐axis dose output (cGy/MU) and percent dose versus depth (PDD) data that show the effects of curvature on results computed by the Varian eMC v15.6 algorithm using 6, 9, 12, 16, and 20 MeV electron beams incident on virtual phantoms with curved surfaces. The phantoms were designed to simulate common treatment sites. The dose outputs at the depth of maximum dose (dmax) on the central axis were observed to decrease 0%–14%, and several features of the PDDs for the A10 applicator changed, including up to 12% increased entrance dose. These dosimetric changes have the greatest effect on treatment sites with a radius of curvature of 10 cm or less, such as the scalp, nose, neck, and extremities. The concept of applying a curvature correction factor based on relative output data is presented to help clinical users mitigate discrepancies between calculations performed by simple monitor unit verification systems and accurate treatment planning dose algorithms.

The optimal functionalities of materials often appear at phase transitions involving simultaneous changes in the electronic structure and the symmetry of the underlying lattice. It is experimentally challenging to disentangle which of the two effects—electronic or structural—is the driving force for the phase transition and to use the mechanism to control material properties. Here we report the concurrent pumping and probing of Cu₂S nanoplates using an electron beam to directly manipulate the transition between two phases with distinctly different crystal symmetries and charge-carrier concentrations, and show that the transition is the result of charge generation for one phase and charge depletion for the other. We demonstrate that this manipulation is fully reversible and nonthermal in nature. Our observations reveal a phase-transition pathway in materials, where electron-induced changes in the electronic structure can lead to a macroscopic reconstruction of the crystal structure.

Using a melt-mixing technique, ethylene–vinyl acetate (EVA) copolymers based composites containing Multi-Wall Carbon nanotubes (MWCNTs), aluminum trihydrate (ATH), zinc borate (ZB), and gadolinium oxide (Gd 2 O 3 ) were fabricated. Then, the as-prepared samples were irradiated with an electron beam (EB) at the dose range varied from 0 to 275 kGy. Moreover, we investigated the properties of irradiated and unirradiated samples. Morphological observation showed good dispersion of MWCNTs and other additives in EVA. Furthermore, the gel content, mechanical properties, the limit oxygen index (LOI) values of irradiated composites increased to 28.4% after 250 kGy after irradiated. All the conclusions indicated that the comprehensive properties of the WMCNTs/EVA composites were improved by using high energy electron beam irradiation.

The results of an experimental investigation of the effect of cumulation of a beam of runaway electrons formed in a high-voltage nanosecond discharge at a reduced air pressure are presented. The optimal conditions of this effect in a discharge gap in a tubular cathode – grounded planar anode geometry were achieved at an air pressure of ≈5 Pa and an interelectrode gap of 2.75 mm. An electron-beam current pulse is recorded with a high time resolution (up to about 80 ps) behind the flat foil anode. It is found out that due to this effect a through hole is formed in a 20 μm-thick aluminum foil after 2–3 discharge pulses. The results obtained suggest that the electron energy in the second part of the beam current pulse is lower than that in its first part.