Abstract
The idea of in situ transmission electron microscopy (TEM) and its possible ramifications were proposed at the very dawn of electron microscopy, but the translation from theory to practice encountered many technological setbacks, which hindered the feasibility of the most elaborated approaches until recent times. However, the several technological improvements achieved in the last 10–15 years filled this gap, allowing the direct observation of the dynamic response of materials to external stimuli under a vast range of conditions going from vacuum to gaseous or liquid environment. This resulted in a blossoming of the in situ TEM and scanning TEM (STEM) techniques to a new youth for a vast, growing range of applications, which cannot be rightfully detailed in a short span; therefore, this chapter should be intended as a guide highlighting a selection of the most inspiring, recently achieved results.
Keywords
- analytical electron microscopy
- environmental transmission electron microscopy
- in situ transmission electron microscopy
- scanning transmission electron microscopy
- transmission electron microscopy
1. Introduction
The idiom “seeing is believing” is very old and has been often used since its religious inception to the present day as the title of novels, songs, movies, and documentaries. However, it is also the actual utterance of any
Why we titled this chapter “The new youth of the
Due to the current and continuously growing vastness of the
The chapter starts with a section dedicated to the
2. In situ heating TEM experiments in vacuum
Studies involving temperature and its effects on the features and evolution of various systems are most common in a very broad number of different branches, ranging from fundamental research and going to strictly applicative performance issues. Despite the very different focus, all these kind of studies rely on the basic assumption that the goodness and reliability of the results will necessarily go through trying to obtain the most thorough description of the evolution of the system and of the phenomena leading to said evolution. Thus, while TEM stands as the obvious choice for gathering a vast array of accurate direct structural information, the choice of performing
On the other hand, the
In this framework, the evolution observed in the design of heating holders, going from homemade custom ones [9, 10] to commercial furnace-type ones [11, 12] to the most recent developments involving strongly localized micron‐wide heating areas, affected the feasibility of heating experiments.
In furnace‐type heating holders, the annealing is achieved by heating a section located at the tip of the TEM holder, where the TEM grid is lodged and clamped. A heating filament in proximity to the TEM grid is responsible for the heating of this “hot zone,” while the temperature can be measured by a thermocouple or a temperature‐to‐current calibration curve (Figure 1A).
Obviously, the hot region of the furnace must be mechanically stable within the working temperature range in order to minimize the mechanical drift associated with the thermal expansion of the furnace, while being as thermally isolated as possible from the rest of the holder in order to limit the heat conduction to the rest of the tip/holder and the consequent instability in reaching and measuring the correct temperature. Thus, the improvement of this category of holders goes through finding appropriate materials for the different components of the tip and designing a heating system that maximizes both the heating performance and the thermal and mechanical stabilities while minimizing the undesired side effects, such as heat dissipation to the rest of the holder and high power consumption.
From the materials point of view, this implies lowering the coefficient of thermal expansion for the ones used in the furnace, while those used to connect the furnace to the tip must also guarantee low thermal conductivity, since the connections should insulate the furnace against the heat conduction to the holder. Moreover, the rest of the tip should have high heat capacity in order to minimize the heating by irradiation coming from the furnace, thus keeping the holder as close as possible to room temperature. The results achieved with regard to the materials must be supported by improving the design of the holder in order to increase its ease of use and its efficiency in terms of performance vs. power consumption. This means, for example, trying to minimize the size of the furnace (and consequently increasing the available heating rates while decreasing the power consumption necessary for any heat treatment) or designing tips that decrease the heat dispersion from the furnace. However, one inherent problem of indirect‐heating holders, such as the furnace‐based ones, lies in the gradient of temperature occurring between the heating furnace and the TEM grid during the annealing: this difference can be minimized in stable temperature conditions, but it still induces a transient state of thermal imbalance and mechanical drift due to thermal expansion.
In this framework, the run for improving the performance of heating holders leads to the introduction of different solutions that abandoned the furnace‐based architecture for annealing TEM samples (Figure 1B and C). Kamino holders [13] adopted heating wires as a direct source of Joule heating and as a support for the TEM sample: this architecture allows for a direct heating of the sample and higher annealing temperatures but lacks versatility, because samples need to be supportable by the heating wire. A further step in this direction is represented by heating holders based on MEMS (microelectromechanical systems) chips technology [14, 15]. These chips are constituted by a semiconductor (usually Si or Si‐based material) as main body, overlaid by a thin film and featuring a small, electron‐transparent area devoted to the heating and subsequent TEM analysis, thus effectively combining the heating element and the TEM grid in the same object. The presence of a support film allows for greater versatility in terms of possible samples, while dedicated conductive wirings provide the heating and temperature measurements of the heating area in a fashion similar to the furnace‐type holders: a heating wire acts as an electrical furnace, while a second one is used as a temperature probe against a resistance‐to‐temperature calibration curve. Given the small dimensions of the heating area (usually less than 0.1 mm2 wide) with respect to those of the whole chip, choosing a material with high thermal conductivity enables the chip itself to act both as a thermal sink with respect to the heating area and as an insulating buffer with respect to the holder. On the other hand, the engineering of a miniaturized heating area with low heat capacity implies using smaller heating currents. The combination of these characteristics allows faster temperature ramps and faster cooling rates by the sole variations in heating current values, resulting in a more precise control over the desired temperatures and an overall expansion of the possibilities of annealing experiments.
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig1.png)
Figure 1.
(A) Top view of a furnace‐based heating holder. The circular hole at the center of the furnace serves as lodging for the TEM grid. Adapted with permission from [
Considering these innovations in the more general framework of the recent achievements of TEM, the possibility of performing
2.1. In situ TEM heating in Au nanoparticles
The study of colloidal metallic nanoparticles (NPs) has been a major research subject during the past decades, at first to show, then to study and modify their properties for a vast array of possible applications, such as biomedical, sensor technologies, energy storage and nanocatalysis. The development and improvement of imaging techniques such as TEM allowed a clearer comprehension on the connections between structural characteristics and physical properties at the nanoscale, which are required to understand and optimize their use in diverse applications.
In this general context, Au NPs were a constant object of interest in studies describing different synthetic methods and morphologies, their properties, and their possible applications [16–20]. However, regardless of the particular field of application, any engineering attempt would benefit from a detailed analysis of the morphological and structural transformations happening at the nanoscale. This is the reason for developing and improving a nanoscale phase diagram for Au NPs, i.e., a predictive map of their structural‐, morphology‐, and temperature‐dependent stable configurations. Previous experimental and theoretical studies on nanogold [21, 22] were recently improved thanks to
The relationship between theoretical and experimental data with regard not only to the structural evolution of the NPs but also to their so‐called roughened and melting states proved the suitability of this course of action for obtaining a full structural characterization. In fact, a similar approach was recently tried by Baumgardner [25], who studied the structural evolution of a heterogeneous Au:Fe2O3 NP system at elevated temperatures by
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig2.png)
Figure 2.
(A) Representative HRTEM images showing the phase variations of a 7.5 nm wide Au NP as a function of temperature. Adapted with permission from [
On the other hand,
Conversely, the mobility and sintering of Au NPs is a drawback in the case of catalysis, where stability problems caused by deactivation due to NP sintering at high temperatures are well‐known problems for metallic NP‐based catalysts. Thus, a deeper comprehension of the sintering mechanism of NPs inside a porous matrix is a basic research study with immediate applicative repercussions. Liu et al. [28] studied the migration of Au NPs inside the ordered channels of mesoporous silica via
2.2. In situ chemical reactions of semiconductor‐based materials
Semiconductors represent another broad research subject in the fields of chemistry and material science, but recent studies conducted on these systems offer a different prospective on the role and possibilities of
In fact, while colloidal synthesis is a well‐known route to synthesize and fine‐tune NPs with well‐defined crystal structure, shape and size [29, 30],
In this context, the studies by Hellebusch et al. [34] and Hudak et al. [35] represent perfect examples of basic research of immediate applicative interest, since both present stability tests for materials that are already being used as building blocks in a vast range of applications. In particular, Hellebusch et al. [34] investigated the
On the other hand, Hudak et al. [35] investigated the dissolution of Au‐decorated SnO2 nanowires.
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig3.png)
Figure 3.
(A) CdSe NRs sublimation during
An alternative approach to
Also, De Trizio et al. [37] obtained a new phase through substitution of both cationic and anionic atomic species by performing
Thus,
2.3. In situ TEM heating for graphene studies
Graphene, with its unique physicochemical properties [38–40], has been the subject of various studies voted to better understand its properties in response to external
In particular, the control over orientation during the growth of the graphene layer has been an ongoing issue since graphene layers were first produced by mechanical exfoliation of bulk graphite by Gemin and Novoselov in 2004 [41] regardless of the growth technique (CVD [42], thermal decomposition of SiC [43] and molecular beam epitaxy (MBE) [44]), and investigating its growth process is a mandatory prerequisite for a successful application. In this perspective,
Given the significance of the etching and curing effects in the graphene layer at high temperatures [47, 48], Kano et al. [49] investigated the structure and dynamics of Cu atoms embedded in single‐layer graphene by aberration‐corrected TEM operating at 80 kV while heating the sample through a MEMS‐based chip. Cu atoms could replace C atoms of graphene under irradiation by a focused electron beam, more easily when residual oxygen and hydrocarbon contaminations were present. However, the Cu‐C substitution was in competition with Cu evaporation: analyzing these processes during
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig4.png)
Figure 4.
(A) Sequential ADF (annular dark‐field) images showing graphene from the step edge of the BLG at 500°C. The dashed magenta line indicates the initial 2nd layer step edge, while the cyan dot line highlights the rotated 2+ layer. Green arrows show the single Si atoms at the step edge and a white arrow indicates the pinned Si atom. Adapted with permission from [
The effects of temperature on graphene are not limited to the cleaning and restoration of the lattice: in fact, those same temperature‐dependent effects can be exploited to perform nanofabrication. Nanopores embedded in thin membranes attracted special interest for their potential application in label‐free, single‐molecule detection of chemicals or biomolecules [52, 53]. Xu showed that a strongly focused 300 kV electron beam could be used to sculpt freestanding monolayer graphene with close‐to‐atomic precision in the STEM mode while heating the sample at 600°C [54]. The same electron beam with different scanning dwell times was used for sculpting and imaging: this allowed an immediate switching between sculpting and imaging and consequently fine‐tuning the shape of the sculpted lattice. The effect of temperature was clarified by performing sculpting at 20, 400, 600, 700, and 800°C under identical STEM conditions while varying dwell times. The sculpting was successfully performed between 400 and 700°C, but it led to the contamination of the specimen at 20°C and it was not possible, even with large dwell time, at 800°C likely due to self‐repair process being faster than C removal. More in detail, the experiment consisted in three steps: preparation, sculpturing, and inspection. The preparation of the sculpting area was performed in imaging mode at 600°C so that any isolated defects created by the electron beam were removed by self‐repair of the lattice. Then, in sculpting mode, using a longer dwell time, several adjacent carbon atoms were knocked‐out to prevent self‐repair of the graphene lattice; extending the initial hole in a predefined direction it was possible to shape the graphene in a pattern with a precise position, size, and orientation. Finally, switching again to the imaging mode the sculpted pattern was inspected without introducing damages. Furthermore, the patterned graphene nanostructures were stable after being cooled to room temperature and stored in air. He also studied the stability of nanopores, developing a method to eliminate the dangling bonds at the pores edge in monolayer graphene and creating the so‐called closed edge nanopores by using electron beam irradiation during
2.4. New directions and perspectives of in situ TEM annealing
The resurgence of
A couple of recent studies dealing with the role of carbon with regard to
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig5.png)
Figure 5.
(A) TEM images collected during
Romankov and Park [58] approached the problem of C contribution to
Recently,
A good example is given by carbon nanotubes (CNTs), which lacked a detailed nucleation study, despite their popularity for many possible applications. While their nucleation was generally ascribed to a generic vapor‐liquid‐solid (VLS) mechanism, the study conducted by Tang et al. [59] was specifically focused on shedding light on these aspects. The nucleation and growth of CNTs were studied by using an unconventional
The study of Casu et al. [61] provides a further example, focusing on modifications occurring during CE reactions in solid state at the nanoscale during
3. In situ gas‐solid reactions in environmental (S)TEM
Chemical reactions between gaseous phases and solid materials represent a challenging topic not only for the basic scientific research but also for important industrial applications. Since the dawn of the TEM technique, scientists tried to locally modify the environment around the specimen by introducing liquid or gaseous phases in order to study the materials under reactive or real environments [62–64]. These attempts clashed with the “classical” configuration of the TEM, which normally needs high vacuum conditions (1 × 10–7 Torr) [65] to protect the electron gun, to prevent contamination of the sample, and to avoid any blurring effect due to additional scattering of the electron beam with atoms that are not part of the specimen. The challenge was then to increase the gas pressure in a localized and controlled environment around the specimen so that temperature, gas composition, and pressure could be tuned without compromising the performance of the microscope itself. Scientists and manufactures developed two confinement methods for gaseous phases to achieve controlled environment TEM (E‐TEM): (i) differentially pumped systems, featuring modified TEM column and vacuum system [66–72], and (ii) window‐closed cells designed
Nowadays, coupling these two methods with the exceptional spatial and time resolution capabilities of state‐of‐the‐art (S)TEMs and detectors, such as those used in EDS and EELS, creates an extremely powerful tool for structural and chemical analyses of materials up to the atomic scale and over the reaction time [79]. However, the introduction of gases to create an environmental cell inside the TEM implies some additional limitations, i.e., the degradation of signal and spatial resolutions. The presence of an external gas species implies a direct rise in the number of molecules along the path L of the electron beam in the vicinity of the specimen and, in turn, is responsible for additional scattering events (
where
3.1. The differentially pumped system
The differentially pumped system approach relies on a modified TEM setup to perform environmental studies. In this case, the environment cell (E‐Cell), generally intended as the experimental chamber where the specimen comes in contact with user‐introduced gaseous species, is constituted by the portion of TEM column around the sample that is limited by a double series of additional apertures with small holes, which are positioned in correspondence with the objective lens pole pieces to confine the gaseous phases. Two additional sets of apertures along the column combined to a differential pumping system create zones of decreasing pressure between the high pressure zone of the E‐Cell and the high vacuum of the other parts of the TEM column, thus protecting the electron gun from any gas coming from the E‐Cell (Figure 6A).
This architecture allows the separate vacuum control of the E‐Cell from the rest of the TEM column so that all the volume around the sample delimited by the objective lens can be filled with gases at low pressure and evacuated independently. The introduction of external gases implies that the E‐Cell needs to be connected to an external gas manifold and flow controller system equipped with gas reservoir tanks, unreactive pipelines, and pressure gauges for any tuning and monitoring procedures [71] but no modification is necessary with regard to the holder and any type of tilting and heating TEM holders can be used to perform
The main advantage of the differential pumping is that it is an
In addition, the imaging resolution is not only affected by the presence of gases, but it is also influenced by additional electro‐optical and microscope‐related parameters with opposite effects, i.e., the electron dose and the primary electron energy. In fact, under the same conditions of E‐Cell gas pressure and primary high tension, reducing the electron‐dose increases the spatial resolution (Figure 6B) [84], while reducing the high tension worsens the spatial resolution (Figure 6C) [85]. These effects can be explained thinking that a low electron dose will lower the electron density of the beam and the overall number of
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig6.png)
Figure 6.
(A) Schema of a differentially pumped TEM system after [
In general, the combination of
In particular, studying the modifications occurring to catalysts in different temperature and pressure regimes is a focal point for assessing the best working conditions and comprehending variations in catalytic performance. This is the case of cuprous oxide (Cu2O) NPs, which represents an active photocatalyst for hydrogen production by water splitting through direct irradiation with visible light (
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig7.png)
Figure 7.
(A) HAADF STEM images of a Cu2O nanocube before (left) and 30 min after (right) the photocatalytic reaction. The corresponding EEL spectra of the peripheral region (below) show the coexistence of metallic Cu portions (marker 1) in the Cu2O nanocube (Marker 2). Adapted with permission from [
On the other hand, E‐TEM is also a powerful tool for direct observation in more applicative‐inclined studies, devoted to test and observe the performance and limits of materials with more immediate practical repercussions. Such is the case of the study on yttria‐stabilized zirconia (YSZ) NPs as a treatment device for soot exhaust products by their oxygen channeling capability [90].
3.2. The window‐closed E‐cell
The window‐closed cell is the main alternative to the differentially pumped system for environmental TEM analysis. In this case, the E‐cell is incorporated into the tip of a dedicated TEM holder and uses two parallel electron‐transparent windows to confine the sample and the gases inside a tiny‐volume nanoreactor (Figure 8A), while no modification to the TEM column is required. By reducing the volume to a small, closed layer around the specimen, the gaseous phases can reach pressures above one atmosphere [92–94], while the nanoreactor can be safely inserted in the TEM column. The main advantage, other than the higher working pressures, is that this setup can be installed in different TEMs without any modification to the column and vacuum system with a direct saving of costs of purchasing and maintenance.
The confinement diaphragms of the window‐closed cell must have some fundamental prerequisites. Namely, they must (i) be electron-transparent, (ii) be strong enough to confine the pressurized gas, and (iii) provide a low diffraction contribution in order to reduce any effects of diffraction contrast and limit the superposition of additional periodic patterns to the “proper” signals coming from the sample [95]. These are the reasons why the diaphragms are made of thin and amorphous materials with low average atomic number (e.g., carbon, silicon nitride), thus also minimizing their
Also, in this configuration the gas pressure and the temperature inside the cell can be monitored and varied continuously, up to the instrumental limit. The holder is generally connected to an external gas line equipped with gas reservoir tanks, unreactive pipelines, and manometer pressure gauges capable to control the pressure from few mbars to few bars, while a dedicated vacuum pump is used for purging operations [93].
In this regard, the introduction of micromechanical system (MEMS) technology led to important improvements in the mechanical characteristics, design, and performance of window materials and in the engineering of holders with respect to previously available setups (Figure 8B) [92, 94, 97]. The last generations of closed cell nanoreactors, obtained via MEMS technology, integrate electron‐transparent diaphragms made of 10 nm thick amorphous silicon nitride, flow gas pipes of a few tens of micrometer wide, micropressure controlling gauges, and microheaters [98, 99]. Usually, the heater system is a metallic spiral strip (e.g., underdoped Pt or Pt‐based alloys) embedded on the lower thin window and the gas path between the windows is in the order of some tens of micrometers, which allows a reduction in the volume of the cell. Moreover, the spiral shape of the heater helps to minimize any spurious magnetic fields interfering with those of the electromagnetic lenses [98] and any thermal gradient upon the sample. The combination of these parameters makes MEMS‐based nanoreactors suitable for HRTEM and HRSTEM imaging in Cs‐corrected microscopes even at atomic scale, as demonstrated, e.g., by the study of Allard et al. [93] on catalytic nanomaterials, which exhibited atomic columns resolution under vacuum in Au NPs grown on Fe2O3 and in Rh nanocrystals on CaTiO3 under pressures up to 1 atm. Ultimately, the improvement in performance over a wide range of working pressures and temperatures and the adaptability to different (S)TEMs without any modification of columns and vacuum systems provide the window‐closed cells a high experimental flexibility, which makes them valuable in a variety of scientific studies devoted to the
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig8.png)
Figure 8.
(A) Schema of TEM holder with window‐closed cell; (B) MEMS‐based nanoreactor. Top: Schematic lateral cross section with the electrical contact for the heater; middle: schematic 3D view of the MEMS nanoreactor; bottom: active area, featuring the microheater spiral (in white) with ovaloid electron‐transparent windows and circular spacers. Adapted with permission from [
In this context, Sun et al. adapted a wet cell they previously developed into a closed‐cell setup for
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig9.png)
Figure 9.
(A) Metallic evolution of Ag NPs in an air‐filled cell after exposure. Top, from left to right: after 0 s with 0.18 A cm2 current density; after 20 s with 0.18 A cm2 current density (a new grain is indicated by a white arrow); after 0 s with 0.44 A cm2 current density; after 20 s with 0.44 A cm2 current density. Bottom, from left to right: after 0 s with 0.66 A cm2 current density; after 20 s with 0.66 A cm2 current density; after 20 s with 0.72 A cm2 current density; after 20 s with 0.8 A cm2 current density (the black arrow marks the vertical alignment of the AgO vapor phase). Adapted with permission from [
More recently, Vendelbo et al. [97] used a MEMS‐based nanoreactor to study
4. In situ (S)TEM imaging of liquid specimens
As mentioned in the Section 1, since the invention of the electron microscope, one of the main scientific challenges has always been the imaging of liquid or wet samples. Even if this is usually possible by using light/fluorescence/confocal microscopy, and even taking into account the most recent and dramatic resolution improvements achieved due to the super‐resolution approaches [102], its resolution (currently less than 100 nm) is still far from that of any electron microscope and represents a strong limit for nanoscale analyses of liquid samples. That being said, this section deals with the methods and devices that allow to achieve much higher resolution of liquid/wet samples performing
A brief historical overview looks helpful in understanding what were, since the first decades of electron microscopy, the main limitations related to the possibility to perform
A further and strong novelty was then proposed in the work of Parsons [66], who described a new kind of experimental design to perform
A variation of E‐TEM is that shown by Gai in [106], where both environmental and high‐resolution TEM (EHRTEM) were shown with a double possible configuration: first, a specific microreactor inserted inside the E‐Cell of the EHRTEM column enables studies of thermally driven gas‐solid reactions, while keeping an atomic resolution. Similarly, a way to develop
However, what was mainly developed in the following years and so far to perform
More recently, double window‐based E‐Cells for liquids were then and again used for
The major improvement achieved for the development of specimen holders capable to allow
In the following, we first deal with the equations needed to determine the final point resolution when an
4.1. The point resolution when using an in situ sample holder for liquids
4.1.1. TEM
To determine how to calculate the final point resolution when using an
where
Thus, taking into account what indicated by Eq. (2) to look at any liquid sample (i.e., at a solid sample surrounded by a liquid environment) by TEM using the parallel electron beam geometry, the highest attainable resolution is obtained for solid objects surrounded by liquid in a configuration where electrons have to pass the lowest possible liquid volume after having crossed the solid objects, in order to minimize the energy broadening that they suffer in scattering with the liquid's molecules. For this reason, the solid part of the sample should be put onto the internal side of that E‐Cell windows from which the electrons definitely exit from the E‐Cell or, analogously, if the solid objects are homogeneously distributed all over the liquid the best choice to image them by TEM is that to focalize the ones closest to the lower E‐Cell's window. In other words, to obtain the best resolution, the objective lens focal plane should be placed as near as possible to the internal side of the lower E‐Cell's window. Figure 10A shows this experimental configuration.
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig10.png)
Figure 10.
Different possible configurations for electron microscopy in liquid. (A) TEM imaging of nanoparticles in a liquid fully enclosed between two electron‐transparent windows. Adapted with permission from [
4.1.2. STEM
Differently from the TEM geometry, in which a parallel electron beam is used to illuminate whole areas of the sample, in the STEM the imaging is performed by a convergent beam that scans the sample point by point and where the contrast is then obtained by collecting the electron signal produced by each irradiated point with an appropriate detector. Even considering that the transmitted beam is the simplest way to form an image (the so‐called Bright field mode), to image the contrast due to small but atomically heavy objects (like NPs) dispersed in a lighter liquid medium, the signal emitted with an high angle of divergence is usually the one collected to form the STEM image, being this STEM detection's geometry called HAADF. In such a case, the contrast is due to the fact that the detected signal's intensity is roughly proportional to
where
Thus, the highest resolution for the STEM imaging of an object within a liquid is achieved when the object is at the entrance side of the sample. Moreover, keeping the specimen holder filled with the same water volume, the NP STEM imaging will be performed with a resolution in principle quite higher than the one obtainable by using a TEM imaging.
According to Eq. (3), a gold NP (marker) with a 1.4 nm in diameter can be resolved on a water layer of
4.2. In situ liquid TEM for materials science studies
Just as short overview of the different fields of application of
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig11.png)
Figure 11.
(A) Sketch of the liquid cells’ components. Adapted with permission from [
In 2009, Zheng et al. again used TEM geometry and a double SiN window
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig12.png)
Figure 12.
Growth and coalescence of Pt nanocrystals. (A) Top images: video frames acquired at different time points of exposure to the electron beam are reported, with specific particles labeled by arrows. Bottom image: the number of particles (left axis) and the number of coalescence events (Nc, right axis) vs. time, as measured with a time rate of 2.0 s. Adapted with permission from [
Similarly to what cited above, Evans et al. synthesized PbS NPs using as electrolyte a solution containing lead acetate, poly(vinyl alcohol), isopropyl alcohol, and thioacetamide [114]. The selective decomposition of thioacetamide was again promoted using the illumination with high‐energy electron beam as driving force, and it gave rise to the production of free sulfur ions in solution. Surrounding lead ions then reacted with the free sulfur ions to allow the PbS NPs to nucleate and grow, while the poly(vinyl alcohol) acted as a stabilizing agent. However, two quite important improvements were shown in the work of Evans et al. and consisted in (a) using a continuous flow of reactants, drawn in and out from the E‐Cell by appropriate microfluidic lines and (b) monitoring the processes occurring inside the E‐Cell by using a spherical aberration corrected STEM, with higher resolution than the one attainable using a conventional TEM, for the reasons explained above.
4.3. In situ liquid TEM for biological sciences studies
For biological purposes, both E‐TEM and sealed E‐Cells for liquid specimen holders have been used, with a large predominance of the sealed ones. However, a premise is crucial before showing some examples. When using any EM imaging technique, either TEM or SEM based, no living specimen could be directly looked at without destroying it. That is due to the intrinsic conditions needed for any electron microscope to work (high vacuum and radiation damage due to the electrons‐matter interactions) that are incompatible with the high water content, low density, and very low hardness of any living organism. To look at any living matter
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig13.png)
Figure 13.
(A) Top image: single Si microchip with an electron‐transparent SiN window. The sizes of the microchip are 2.0 × 2.3 × 0.3 117. Bottom image: sketch of a microfluidic chamber constituted by two Si microchips such as the ones presented in the top image and showing the liquid flow direction. Adapted with permission from [
As first example of study of biological living matter by
As already mentioned and shown by Eq. (3), the use of STEM allowed to achieve a dramatically increased resolution and to image by using HAADF geometry even very small heavy particles dispersed in a light liquid medium. This was the case of Au‐labeled eukaryotic fibroblast cells (COS7) immersed in a several micrometer‐thick liquid layer [107, 109]. In both the papers a flow liquid E‐Cell was used, allowing the aqueous solution to pour through the E‐Cell and around the whole fibroblast cells. The experimental configuration is reported in Figure 13A. The cells were grown, then labeled, and finally fixed prior to be inserted in the flow E‐Cell, on the internal side of the silicon nitride film that was finally placed to seal the upper part of the E‐Cell, in order to maximize the STEM resolution according to Eq. (3). The cells’ immunolabeling was realized by using gold NPs sizing 10 nm, in order to target the epidermal growth factor (EGF) molecules bound to the cellular EGF receptors. Thus, using a water layer 10 μm thick, the theoretical resolution limit determined by using Eq. (3) was found to be equal to 1.9 nm. In agreement with that, the 10 nm sized labeling gold NPs were detected with a spatial resolution of about 4 nm, as shown in Figure 13B and C, using the STEM in HAADF geometries, and performed with a beam accelerated by a voltage of 200 kV and a dwell time of 20 μs. If it is not weird that the electron beam did not perturb the fixed cells, it is however remarkable that for the dose used (7 × 104 electrons per nm2) and within the flowing liquid no visible damage consequences were observed on the spatial distribution of the labeling NPs on the cells.
As last and most recent example the results achieved by Pohlmann
![](http://cdnintech.com/media/chapter/51150/1512345123/media/fig14.png)
Figure 14.
(A) First row, left images: sketches of microchip with integrated microwells (10 μm in diameter) functionalized to specifically capture GS9‐6/NOTCH+ glioblastoma stem cells; right images: comparison between the functionalized microwells (called “capture”) and the negative control, i.e., identical microwells not treated for functionalization and then not able to tether GSCs. Second row: sketch showing a cross‐sectional view of the microfluidic system containing GSC positioned in the TEM column. Adapted with permission from [
5. Conclusions
In this chapter, some of the most recent developments for the
References
- 1.
Freitag B, Knippels G, Kujawa S, Van der Stam M, Hubert D, Tiemeijer PC, Kisielowski C, Denes P, Minor A, Dahmen U. First performance measurements and application results of a new high brightness Schottky field emitter for HR S/TEM at 80–300 kV acceleration voltage. Microsc. Microanal. 2008; 14:1370–1371. DOI: 10.1017/S1431927608087370. - 2.
Haider M, Uhlemann S, Schwan E, Rose H, Kabius B, Urban K. Electron microscopy image enhanced. Nature 1998; 392:768–769. DOI: 10.1038/33823. - 3.
Krivanek OL, Dellby N, Lupini AR. Towards sub Angstrom electron beams. Ultramicroscopy. 1999; 78:1–11. DOI: 10.1016/S0304 3991(99)00013 3. - 4.
Tiemeijer PC, Van Lin JHA, De Long AF. First results of a monochromatized 200 kV TEM. Microsc. Microanal. 2001; 7:234–235. - 5.
Kasper E. Field electron emission systems. In: Barer R, Cosslett VE, editors. Advances in Optical and Electron Microscopy. Vol. 8. Academic, London. p. 207; 1982. - 6.
Von Harrach HS, Dona P, Freitag B, Soltau H, Niculae A, Rohde M. An integrated multiple silicon drift detector system for transmission electron microscopes. J. Phys. Conf. Ser. 2010; 241:012015. DOI: 10.1088/1742 6596/241/1/012015. - 7.
Gubbens A, Barfels M, Trevor C, Twesten R, Mooney P, Thomas P, Menon N, Kraus B, Mao C, McGinn B. The GIF quantum, a next generation post column imaging energy filter. Ultramicroscopy 2010; 110:962–970. DOI: 10.1016/j.ultramic.2010.01.009. - 8.
Ruskina RS, Yub Z, Grigorieff N. Quantitative characterization of electron detectors for transmission electron microscopy. J. Struct. Biol. 2013; 184:385–393. DOI: 10.1016/j.jsb.2013.10.016. - 9.
Heinemann K, Poppa H. Direct observation of small cluster mobility and ripening. Thin Solid Films. 1976; 33:237–251. DOI: 10.1016/0040 6090(76)90084 5. - 10.
Ruault MO, Chaumont J, Bernas H. Transmission electron microscopy study of ion implantation induced Si amorphization. Nucl. Instrum. Methods Phys. Res. 1983; 209:351–356. DOI: 10.1016/0167 5087(83)90822 0. - 11.
Chen SH, Zheng LR, Carter CB, Mayer JW. Transmission electron microscopy studies on the lateral growth of nickel silicides. J. Appl. Phys. 1985; 57:258–263. DOI:10.1063/1.335482. - 12.
Dannenberg R, Stach E, Groza JR, Dresser BJ. TEM annealing study of normal grain growth in silver thin films. Thin Solid Films. 2000; 379:133–138. DOI: 10.1016/S0040 6090(00)01570 4. - 13.
Kamino T, Saka H. A newly developed high resolution hot stage and its application to materials characterization. Microsc. Microanal. Microstruct. 1993; 4:127–135. DOI:10.1051/mmm:0199300402 3012700. - 14.
Zhang M, Olson EA, Twesten RD, Wen JG, Allen LH, Robertson IM, Petrov I. In situ transmission electron microscopy studies enabled by microelectromechanical system technology. J. Mater. Res. 2005; 20:1802–1807. DOI: 10.1557/JMR.2005.0225. - 15.
Allard LF, Bigelow WC, Jose Yacaman M, Nackashi DP, Damiano J, Mick SE. A new MEMS based system for ultra high resolution imaging at elevated temperatures. Microsc. Res. Tech. 2009; 72:208–215. DOI: 10.1002/jemt.20673. - 16.
Sperling RA, Rivera Gil P, Zhang F, Zanella M, Parak WJ. Biological applications of gold nanoparticles. Chem. Soc. Rev. 2008; 37:1896–1908. DOI: 10.1039/b712170a. - 17.
DeLong RK, Reynolds CM, Malcolm Y, Schaeffer A, Severs T, Wanekaya A. Functionalized gold nanoparticles for the binding, stabilization, and delivery of therapeutic DNA, RNA, and other biological macromolecules. Nanotechnol. Sci. Appl. 2010; 3:53–63. DOI: 10.2147/NSA.S8984. - 18.
Zhou ZY, Tian N, Li JT, Broadwell I, Sun SG. Nanomaterials of high surface energy with exceptional properties in catalysis and energy storage. Chem. Soc. Rev. 2011; 40:4167–4185. DOI: 10.1039/c0cs00176g. - 19.
Li N, Zhao P, Astruc D. Anisotropic gold nanoparticles: synthesis, properties, applications, and toxicity. Angew. Chem. Int. Ed. 2014; 53:1756–1789. DOI: 10.1002/anie.201300441. - 20.
Langille MR, Personick ML, Zhang J, Mirkin CA. Defining rules for the shape evolution of gold nanoparticles. J. Am. Chem. Soc. 2012; 134:14542–14554. DOI: 10.1021/ja305245g. - 21.
Koga K, Ikeshoji T, Sugawara KI. Size and temperature dependent structural transitions in gold nanoparticles. Phys. Rev. Lett. 2004; 92:115507. DOI: 10.1103/PhysRevLett.92.115507. - 22.
Kuo CL, Clancy P. Melting and freezing characteristics and structural properties of supported and unsupported gold nanoclusters. J. Phys. Chem. B. 2005; 109:13743–13754. DOI: 10.1021/jp0518862. - 23.
Barnard AS, Young NP, Kirkland AI, van Huis MA, Xu H. Nanogold: a quantitative phase map. ACS Nano. 2009; 3:1431–1436. DOI: 10.1021/nn900220k. - 24.
Young NP, van Huis MA, Zandbergen HW, Xu H, Kirkland AI. Transformations of gold nanoparticles investigated using variable temperature high resolution transmission electron microscopy. Ultramicroscopy. 2010; 110:506–516. DOI: 10.1016/j.ultramic.2009.12.010. - 25.
Baumgardner WJ, Yu Y, Hovden R, Honrao S, Hennig RG, Abruna HD, Muller D. Nanoparticle metamorphosis: an in situ high temperature transmission electron microscopy study of the structural evolution of heterogeneous Au:Fe2O3 nanoparticles. ACS Nano. 2014; 8:5315–5322. DOI: 10.1021/nn501543d. - 26.
Figuerola A, van Huis M, Zanella, M, Genovese A, Marras S, Falqui A, Zandbergen HW, Cingolani R, Manna L. Epitaxial CdSe Au nanocrystal heterostructures by thermal annealing. Nano Lett. 2010; 10:3028–3036. DOI: 10.1021/nl101482q. - 27.
Lavieville R, Zhang Y, Casu A, Genovese A, Manna L, Di Frabrizio E, Krahne R. Charge transport in nanoscale “all inorganic” networks of semiconductor nanorods linked by metal domains. ACS Nano. 2012; 6:2940–2947. DOI: 10.1021/nn3006625. - 28.
Liu Z, Che R, Elzatahry AA, Zhao D. Direct imaging Au nanoparticle migration inside mesoporous silica channels. ACS Nano. 2014; 8:10455–10460. DOI: 10.1021/nn503794v. - 29.
Costi R, Saunders AE, Banin U. Colloidal hybrid nanostructures: a new type of functional materials. Angew. Chem. Int. Ed. 2010; 49:4878–4897. DOI: 10.1002/anie.200906010. - 30.
Jun YW, Choi JS, Cheon J. Shape Control of Semiconductor and Metal Oxide Nanocrystals through Nonhydrolytic Colloidal Routes. Angew. Chem. Int. Ed. 2006; 45:3414–3439. DOI: 10.1002/anie.200503821. - 31.
Zheng H, Smith RK, Jun YW, Kisielowski C, Dahmen U, Alivisatos AP. Observation of single colloidal platinum nanocrystal growth trajectories. Science. 2009; 324:1309–1312. DOI: 10.1126/science.1172104. - 32.
Asoro MA, Desiderio K, Ferreira PJ. In situ transmission electron microscopy observations of sublimation in silver nanoparticles. ACS Nano. 2013; 7:7844–7852. DOI: 10.1021/mn402771j. - 33.
Li H, Zanella M, Genovese A, Povia M, Falqui A, Giannini C, Manna L. Sequential cation exchange in nanocrystals: preservation of crystal phase and formation of metastable phases. Nano Lett. 2011; 11:4964–4970. DOI: 10.1021/nl202927a. - 34.
Hellebusch DJ, Manthiram K, Beberwyck BJ, Alivisatos AP. In situ transmission electron microscopy of cadmium selenide nanorod sublimation. J. Phys. Chem. Lett. 2015; 6:605–611. DOI: 10.1021/jz502566m. - 35.
Hudak BM, Chang YJ, Yu L, Li G, Edwards DN, Guiton BS. Real time observation of the solid liquid vapor dissolution of individual tin(IV) oxide nanowires. ACS Nano. 2014; 8:5441–5448. DOI: 10.1021/nn5007804. - 36.
Yalcin AO, Fan Z, Goris B, Li WF, Koster RS, Fang CM, Van Blaaderen A, Casavola M, Tichelaar FD, Bals S, Van Tendeloo G, Vlugt TJH, Vanmaekelbergh D, Zandbergen HW, Van Huis MA. Atomic resolution monitoring of cation exchange in CdSe PbSe heteronanocrystals during epitaxial solid–solid–vapor growth. Nano Lett. 2014; 14:3661–3667. DOI: 10.1021/nl501441w. - 37.
De Trizio L, De Donato F, Casu A, Genovese A, Falqui A, Povia M, Liberato M. Colloidal CdSe/Cu3P/CdSe and their evolution upon thermal annealing. ACS Nano. 2013; 7:3997–4005. DOI: 10.1021/nn3060219. - 38.
Geim AK, Novoselov KS. The rise of graphene. Nat. Mater. 2007; 6: 183–191. DOI: 10.1038/nmat1849. - 39.
Balandin AA, Ghosh S, Bao W, Calizo I, Teweldebrhan D, Miao F, Lau CN. Superior thermal conductivity of single layer graphene. Nano Lett. 2008; 8:902–907. DOI:10.1021/nl0731872. - 40.
Soldano C, Mahmood A, Dujardin E. Production, properties and potential of graphene. Carbon. 2010; 48:2127–2150. DOI: 10.1016/j.carbon.2010.01.058. - 41.
Novoselov KS, Geim AK, Morozov SV, Jiang D, Zhang Y, Dubonos SV, Grigorieva IV, Firsov AA. Electric Field Effect in Atomically Thin Carbon Films. Science. 2004; 306:666–669. DOI: 10.1126/science.1102896. - 42.
Reina A, Jia X, Ho J, Nezich D, Son H, Bulovic V, Dresselhaus MS, Kong J. Large area, few layer graphene films on arbitrary substrates by chemical vapor deposition. Nano Lett. 2009; 9:30–35. DOI: 10.1021/nl801827v. - 43.
Yannopoulos SN, Siokou A, Nasikas NK, Dracopoulos V, Ravani F, Papatheodorou GN. CO2-laser-induced growth of epitaxial graphene on 6H-SiC (0001). Adv. Funct. Mater. 2012; 2:113–120. DOI: 10.1002/adfm.201101413. - 44.
Park J, Mitchel WC, Grazulis L, Smith HE, Eyink KG, Boeckl JJ, Tomich DH, Pacley SD, Hoelscher JE. Epitaxial graphene growth by carbon molecular beam epitaxy (CMBE). Adv. Mater. 2010; 22:4140–4145. DOI: 10.1002/adma.201000756. - 45.
Liu Z, Lin YC, Lu CC, Yeh CH, Chiu PW, Iijima S, Suenaga K. In situ observation of step edge in plane growth of graphene in a STEM. Nat. Commun. 2014; 5:4055. DOI:10.1038/ncomms5055. - 46.
Kotakoski J, Santos Cottin D, Krasheninnikov AV. Stability of graphene edges under electron beam: equilibrium energetics versus dynamic effects. ACS Nano. 2011; 6:671–676. DOI: 10.1021/nn204148h. - 47.
He Z, He K, Robertson AW, Kirkland AI, Kim D, Ihm J, Yoon E, Lee GD, Warner JH. Atomic structure and dynamics of metal dopant pairs in graphene. Nano Lett. 2014; 14:3766–3772. DOI: 10.1021/nl500682j. - 48.
Pi K, McCreary KM, Bao W, Han W, Chiang YF, Li Y, Tsai SW, Lau CN, Kawakami RK. Electronic doping and scattering by transition metals on graphene. Phys. Rev. B. 2009; 80:075406. DOI: 10.1103/PhysRevB.80.075406. - 49.
Kano E, Hashimoto A, Kaneko T, Tajima N, Ohno T, Takeguchi M. Interactions between C and Cu atoms in single layer graphene: direct observation and modelling. Nanoscale. 2016; 8:529–535. DOI: 10.1039/C5NR05913E. - 50.
Ma J, Alfe D, Michaelides A, Wang E. Stone Wales defects in graphene and other planar sp2 bonded materials. Phys. Rev. B. 2009; 80:033407. DOI: 10.1103/PhysRevB.80.033407. - 51.
Ramasse QM, Zan R, Bangert U, Boukhvalov DW, Son YW, Novoselov, KS. Direct experimental evidence of metal mediated etching of suspended graphene. ACS Nano. 2012; 6:4063–4071. DOI: 10.1021/nn300452y. - 52.
Kim MJ, Wanunu M, Bell DC, Meller A. Rapid fabrication of uniformly sized nanopores and nanopore arrays for parallel DNA analysis. Adv. Mater. 2006; 18:3149–3153. DOI:10.1002/adma.200601191. - 53.
Liu K, Feng J, Kis A, Radenovic A. Atomically thin molybdenum disulfide nanopores with high sensitivity for DNA translocation. ACS Nano. 2014; 8:2504–2511. DOI:10.1021/nn406102h. - 54.
Xu T, Xie X, Yin K, Sun J, He L, Sun L. Controllable atomic-scale sculpting and deposition of carbon nanostructures on graphene. Small. 2014; 10:1724–1728. DOI: 10.1002/smll.201303377. - 55.
He K, Robertson AW, Gong C, Allen CS, Xu Q, Zandbergen H, et al. Controlled formation of closed edge nanopores in graphene. Nanoscale. 2015; 7:11602–11610. DOI:10.1039/C5NR02277K. - 56.
Asoro MA, Kovar D, Ferreira PJ. Effect of surface carbon coating on sintering of silver nanoparticles: in situ TEM observations. Chem. Commun. 2014; 50:4835–4838. DOI:10.1039/c4cc01547a. - 57.
Chen C, Hu Z, Li Y, Liu L, Mori H, Wang Z. In Situ high resolution transmission electron microscopy investigation of overheating of Cu nanoparticles. Sci. Rep. 2016; 6:19545. DOI: 10.1038/srep19545. - 58.
Romankov S, Park YC. In situ high temperature TEM observation of material escape from a surface of CoFeNi/Cu/ZrAlO composite into the amorphous carbon layer. J. Alloys Compd. 2015; 632:408–416. DOI: 10.1016/j.jallcom.2015.01.214. - 59.
Tang DM, Liu C, Yu WJ, Zhang LL, Hou PX, Li JC, Li F, Bando Y, Golberg D, Cheng HM. Structural changes in iron oxide and gold catalysts during nucleation of carbon nanotubes studied by in situ transmission electron microscopy. ACS Nano. 2014; 8:292–301. DOI: 10.1021/nn403927y. - 60.
Boston R, Schnepp Z, Nemoto Y, Sakka Y, Hall SR. In situ TEM observation of a microcrucible mechanism of nanowire growth. Science. 2014; 344:623–626. DOI:10.1126/science.1251594. - 61.
Casu A, Genovese A, Manna L, Longo P, Buha J, Botton GA, Lazar S, Kahaly MU, Schwingenschloegl U, Prato M, Li H, Ghosh S, Palazon F, De Donato F, Lentijo Mozo S, Zuddas E, Falqui A. Cu2Se and Cu nanocrystals as local sources of copper in thermally activated in situ cation exchange. ACS Nano. 2016; 10:2406–2414. DOI:10.1021/acsnano.5b07219. - 62.
Marton L. Marton L. Electron microscopy of biological objects (La microscopie electronique des objets biologiques). Bull. Classe. Sci. Acad. Roy Belgique. 1935; 21:553–564 - 63.
Hashimoto H, Naiki T, Eto T, Fujiwara K. High temperature gas reaction specimen chamber for an electron microscope. Jpn. J. Appl. Phys. 1968; 7:946–952. DOI: 10.1143/JJAP.7.946. - 64.
Parsons DF. Structure of wet specimens in electron microscopy. Science. 1974; 186:407–414. DOI: 10.1126/science.186.4162.407. - 65.
Mehraeen S, McKeown JT, Deshmukh PV, Evans JE, Abellan P, Xu P, Reed BW, Taheri ML, Fischione PE, Browning ND. A (S)TEM gas cell holder with localized laser heating for in situ experiments. Microsc. Microanal. 2013; 19:470–478. DOI: 10.1017/S1431927612014419. - 66.
Turner JN, See CW, Ratkowski AJ, Chang BB, Parsons DF. Design and operation of a differentially pumped environmental chamber for the HVEM. Ultramicroscopy. 1981; 6:267–280. DOI: 10.1016/s0304 3991(81)80162 3. - 67.
Lee TC, Dewald DK, Eades JA, Robertson IM, Birnbaum HK. An environmental cell transmission electron microscope. Rev. Sci. Instrum. 1991; 62:1438–1444. DOI:10.1063/1.1142464. - 68.
Boyes ED, Gai PL. Environmental high resolution electron microscopy and applications to chemical science. Ultramicroscopy. 1997; 67:219–232. DOI: 10.1016/S0304 3991(96)00099 X. - 69.
Sharma R. Design and applications of environmental cell transmission electron microscope for in situ observations of gas–solid reactions. Microsc. Microanal. 2001; 7:494–506. DOI: 10.1007/s10005 001 0015 1. - 70.
Hansen TW, Wagner JB. Environmental transmission electron microscopy in an aberration corrected environment. Microsc. Microanal. 2012; 18:684–690. DOI: 10.1017/S1431927612000293. - 71.
Boyes ED, Gai PL. Visualising reacting single atoms under controlled conditions: advances in atomic resolution in situ environmental (scanning) transmission electron microscopy (E(S)TEM). C. R. Physique 2014; 15:200–213. DOI: 10.1016/j.crhy.2014.01.002. - 72.
Kawasaki T, Ueda K, Ichihashi M, Tanji T. Improvement of windowed type environmental cell transmission electron microscope for in situ observation of gas solid interactions. Rev. Sci. Instrum. 2009; 80:113701. DOI: 10.1063/1.3250862. - 73.
Baker RTK, Barber MA, Harris PS, Feates FS, Waite RJ. Nucleation and growth of carbon deposits from the nickel catalyzed decomposition of acetylene. J. Catal. 1972; 26:51–62. DOI: 10.1016/0021 9517(72)90032 2. - 74.
Baker RTK, Harris PS. Controlled atmosphere electron microscopy. J. Phys. E. 1972; 5:793–797. DOI: 10.1088/0022 3735/5/8/024. - 75.
Parkinson GM. High resolution, in situ controlled atmosphere transmission electron microscopy (CATEM) of heterogeneous catalysts. Catal. Lett. 1989; 2:303–307. DOI:10.1007/BF00770228. - 76.
Giorgio S, Joao SS, Nitsche S, Chaudanson D, Sitja G, Henry CR. Environmental electron microscopy (E TEM) for catalysts with a closed E cell with carbon windows. Ultramicroscopy. 2006; 106:503–507. DOI: 10.1016/j.ultramic.2006.01.006. - 77.
de Jonge N, Bigelow WC, Veith GM. Atmospheric pressure scanning transmission electron microscopy. Nano Lett. 2010; 10:1028–1031. DOI: 10.1021/nl904254g. - 78.
Petkov N. In situ real time TEM reveals growth, transformation and function in one dimensional nanoscale materials: from a nanotechnology perspective. ISRN Nanotechnology. 2013; 2013:893060. DOI: 10.1155/2013/893060. - 79.
Hansen TW, Wagner JB. Controlled Atmosphere Transmission Electron Microscopy. Springer International Publishing; Switzerland, 2016. 329 pp. DOI: 10.1007/978 3 319 22988 1. - 80.
Suzuki M, Yaguchi T, Zhang XF. High resolution environmental transmission electron microscopy: modeling and experimental verification. Microscopy. 2013; 62:437–450. DOI: 10.1093/jmicro/dft001. - 81.
Wagner JB, Cavalca F, Damsgaard CD, Duchstein LDL, Hansen TW. Exploring the environmental transmission electron microscope. Micron. 2012; 43:1169–1175. DOI:10.1016/j.micron.2012.02.008. - 82.
Xin HL, Niu K, Alsem DH, Zheng H. In situ TEM study of catalytic nanoparticle reactions in atmospheric pressure gas environment. Microscopy Microanal. 2013; 19:1558–1568. DOI: 10.1017/S1431927613013433. - 83.
Zhang XF, Kamino T. Imaging gas–solid interactions in an atomic resolution environmental TEM. Micros. Today. 2006; 14:16–18. - 84.
Bright AN, Yoshida K, Tanaka N. Influence of total beam current on HRTEM image resolution in differentially pumped E TEM with nitrogen gas. Ultramicroscopy. 2013; 124:46–51. DOI: 10.1016/j.ultramic.2012.08.007. - 85.
Takeda S, Kuwauchi Y, Yoshida H. Environmental transmission electron microscopy for catalyst materials using a spherical aberration corrector. Ultramicroscopy. 2015; 151:178–190. DOI:10.1016/j.ultramic.2014.11.017. - 86.
Jinschek JR, Helveg S. Image resolution and sensitivity in an environmental transmission electron microscope. Micron. 2012; 43:1156–1168. DOI: 10.1016/j.micron.2012.01.006. - 87.
Cavalca F, Laursen, AB, Wagner JB, Damsgaard CD, ChorkendorffIb, Hansen TW. Light induced reduction of cuprous oxide in an environmental transmission electron microscope. Chem. Cat. Chem. 2013; 5:2667–2672. DOI: 10.1002/cctc.201200887. - 88.
Jeangros Q, Hansen TW, Wagner JB, Dunin Borkowski RE, Hébert C, Van herle J, Hessler Wyser A. Oxidation mechanism of nickel particles studied in an environmental transmission electron microscope. Acta Mater. 2014; 67:362–372. DOI: 10.1016/j.actamat.2013.12.035. - 89.
Xin HL, Pach EA, Diaz RE, Stach EA, Salmeron M, Zheng H. Revealing correlation of valence state with nanoporousstructure in cobalt catalyst nanoparticles by in situ environmental TEM. ACS Nano. 2012; 6:4241–4247. DOI: 10.1021/nn3007652. - 90.
Serve A, Epicier T, Aouine M, Cadete Santos Aires FJ, Obeid E, Tsampas M, Pajot K, Vernoux P. Investigations of soot combustion on yttria stabilized zirconia by environmental transmission electron microscopy (E TEM). Appl. Catal. A Gen. 2015; 504:74–80. DOI: 10.1016/j.apcata.2015.02.030. - 91.
Chenna S, Crozier PA. Operando transmission electron microscopy: a technique for detection of catalysis using electron energy loss spectroscopy in the transmission electron microscope. ACS Catal. 2012; 2:2395–2402. DOI: 10.1021/cs3004853. - 92.
Creemer JF, Helveg S, Hoveling GH, Ullmann S, Molenbroek AM, Sarro PM, Zandbergen HW. Atomic scale electron microscopy at ambient pressure. Ultramicroscopy. 2008; 108:993–998. DOI: 10.1016/j.ultramic.2008.04.014. - 93.
Allard LF, Overbury SH, Bigelow WC, Katz MB, Nackashi DP, Damiano J. Novel MEMS based gas cell/heating specimen holder provides advances imaging capabilities for in situ reaction studies. Microsc. Microanal. 2012; 18:656–666. DOI: 10.1017/S1431927612001249. - 94.
Yokosawa T, Alan T, Pandraud G, Dam B, Zandbergen H. In situ TEM on (de)hydrogenation of Pd at 0.5–4.5 bar hydrogen pressure and 20–400°C. Ultramicroscopy. 2012; 112:47–52. DOI: 10.1016/j.ultramic.2011.10.010. - 95.
Doll T, Hochberg M, Barsic D, Scherer A. Micro machined electron transparent alumina vacuum windows. Sens. Actuat. A Phys. 2000; 87:52–59. DOI: 10.1016/S0924 4247(00)00461 1. - 96.
Wu F, Yao N. Advances in windowed gas cells for in situ TEM studies. Nano Energy 2015; 13:735–756. DOI: 10.1016/j.nanoen.2015.03.015. - 97.
Vendelbo SB, Elkjær CF, Falsig H, Puspitasari I, Dona P, Mele L, Morana B, Nelissen BJ, van Rijn R, Creemer JF, Kooyman PJ, Helveg S. Visualization of oscillatory behaviour of Pt nanoparticles catalysing CO oxidation. Nat. Mater. 2014; 13:884–890. DOI:10.1038/nmat4033. - 98.
Creemer JF, Helveg S, Kooyman PJ, Molenbroek AM, Zandbergen HW, Sarro PM. A MEMS reactor for atomic scale microscopy of nanomaterials under industrially relevant conditions. J. Microelectromech. Syst. 2010; 19:254–264. DOI: 10.1109/JMEMS.2010.2041190. - 99.
Yaguchi T, Suzuki M, Watabe A, Nagakubo Y, Ueda K, Kamino T. Development of a high temperature–atmospheric pressure environmental cell for high resolution TEM. J. Electr. Microsc. 2011; 6:217–225. DOI: 10.1093/jmicro/dfr011. - 100.
Sun L, Wook Noh K, Wen JG, Dillon SJ. In situ transmission electron microscopy observation of silver oxidation in ionized/atomic gas. Langmuir 2011; 27:14201–14206. DOI: 10.1021/la202949c. - 101.
Zhang S, Chen C, Cargnello M, Fornasiero P, Gorte RJ, Graham GW, Pan X. Dynamic structural evolution of supported palladium ceria core shell catalysts revealed by in situ electron microscopy. Nat. Commun. 2015; 6. DOI: 10.1038/ncomms8778. - 102.
Hell SW. Far field optical nanoscopy. Science. 2007; 316(5828):1153–1158. DOI:10.1126/science.1137395. - 103.
Abrams IM, McBain JW. A closed cell for electron microscopy. Science. 1944; 100(2595):273–274. DOI: 10.1126/science.100.2595.273. - 104.
Abrams IM, McBain JW. A closed cell for electron microscopy. Appl. Phys. 1944; 15:607–609. DOI: 10.1063/1.1707475. - 105.
Fullam EF. A closed wet cell for the Electron Microscope. Rev. Sci. Instrum. 1972; 43:245–247. DOI: 10.1063/1.1685603. - 106.
Gai PL. Development of wet environmental TEM (wet E TEM) for in situ studies of liquid catalyst reactions on the nanoscale. Microsc. Microanal. 2002; 8:21–28. - 107.
de Jonge N, Peckys DB, Kremers GJ, Piston DW. Electron microscopy of whole cells in liquid with nanometer resolution. PNAS. 2009; 106:2159–2164. DOI: 10.1073/pnas.0809567106. - 108.
de Jonge N, Ross FM. Electron microscopy of specimens in liquid. Nat. Nanotech. 2011; 6:695–704. DOI: 10.1038/nnano.2011.161. - 109.
Dukes M, Peckys DB, de Jonge N. Correlative fluorescence microscopy and scanning transmission electron microscopy of quantum dot labeled proteins in whole cells in liquid. ACS Nano. 2010; 4(7):4110–4116. DOI: 10.1021/nn1010232. - 110.
Pohlmann ES, Patel K, Guo S, Dukes MJ, Sheng Z, Kelly DF. Real time visualization of nanoparticles interacting with glioblastoma stem cells. Nano Lett. 2015; 15:2329–2335. DOI: 10.1021/nl504481k. - 111.
Williamson MJ, Tromp RM, Vereecken PM, Hull R, Ross FM. Dynamic microscopy of nanoscale cluster growth at the solid–liquid interface. Nat. Mater. 2003; 2:532–536. DOI:10.1038/nmat944. - 112.
Radisic A, Vereecken PM, Hannon JB, Searson PC, Ross FM. Quantifying electrochemical nucleation and growth of nanoscale clusters using real time kinetic data. Nano Lett. 2006; 6:238–242. DOI: 10.1021/nl052175i. - 113.
Zheng H, Smith RK, Jun Y, Kisielowski C, Dahmen U, Alivisatos AP. Observation of single colloidal platinum nanocrystal growth trajectories. Science. 2009; 324:1309–1312. DOI: 10.1126/science.1172104. - 114.
Evans JE, Jungjohann KL, Browning ND, Arslan I. Controlled growth of nanoparticles from solution with in situ liquid transmission electron microscopy. Nano Lett. 2011; 11:2809–2813. DOI: 10.1021/nl201166k. - 115.
Liu KL, Wu CC, Huang YJ, Peng HL, Chang HY, Chang P, Hsu L, Yew TR. Novel microchip for in situ TEM imaging of living organisms and bio reactions in aqueous conditions. Lab. Chip. 2008; 8:1915–1921. DOI: 10.1039/B804986F. - 116.
Kim TH, Bae JH, Lee JW, Shin K, Lee JH, Kim MY, Yang CW. Temperature calibration of a specimen heating holder for transmission electron microscopy. Appl. Microsc. 2015; 45:95–100. DOI: 10.9729/AM.2015.45.2.95. - 117.
Tanigaki T, Ito K, Nagakubo Y, Asakawa T, Kanemura T. An in situ heating TEM analysis method for an interface reaction. J. Electron Microsc. (Tokyo). 2009; 58:281–287. DOI: 10.1093/jmicro/dfp020.