Sample Preparation Equipment Documents

A solid-state battery is made of cathode, anode and electrolyte. This type of battery doesn’t use liquid state electrolyte, so it tends to avoid the issues associated with leakage of electrolyte and ignition/explosion. Recently, silicon has been used as an anode material to improve the battery charge capacity (can store ten times more charge as compared to graphite anodes), but some challenges remain in terms of volume expansion during cycling, low electrical conductivity, and instability of the SEI (solid electrolyte interphase) layer caused by repeated volume changes of the Si material.

TEM foil preparation techniques commonly used in geology, material science and cosmochemistry are argon ion milling, ultramicrotomy and the Focused Ion Beam (FIB) technique. In this study we report on Argon Ion Slicing (ArIS), a new gentle preparation method which enables for the first time to prepare super large continuous and relatively smooth electron-transparent thin films (up to 50,000 µm2) suitable for TEM use. So far Argon Ion Slicing was mainly applied on mono- or bi-mineralic samples in material science. We applied and improved this promising new technique on several geo-materials including two meteorite samples to prove the viability of ArIS on complex (polycrystalline, polyphase, porous) natural samples. The successfully obtained continuous electron-transparent thin films comprise an area of 44,000 µm2 for Murchison (CM 2) and 30,000 µm2 for the Allende (CV 3) meteorite samples, respectively. ArIS is a low-energy broad-ion-beam shadowing technique and benefits from an additional protection device (a copper belt). The sample portion directly beneath the belt is protected from the ion beam. The beam "slices off" the protruding sample parts on both sides of the belt and creates a large elongated wedge. Since the developing thin film is located almost parallel to the beam propagation direction, it is almost unaffected from any irradiation damage and a phase dependent preferred thinning is not observed. Rough sample edges were smoothened with a Cross section polisher prior to ArIS treatment, which turned out to be a crucial step to produce super large electron-transparent thin films.

Scanning Electron Microscopes (SEM) support the development of new LIB technologies with morphological observation at the micrometer to nanometer scale, as well as the chemical analysis needed to create high-performance coatings and powders. Ultra-low voltage imaging combined with signal filtering in the SEM allows direct imaging and analysis of battery constituents (anode and cathode) with nanometer resolution. Additionally, one of the important aspects of the analysis is the ability to probe chemistry of the constituents at nm scale (Fig. 1). JEOL FESEM offers the ability to perform microanalysis with energy dispersive spectroscopy (EDS) at extremely low voltages to pinpoint localized makeup of the specimens and, in particular, low atomic number materials such as carbon and fluorine. Moreover, the unique JEOL Soft X-ray spectrometer (SXES) allows researchers to analyze Li.

A method for directly observing the ferroelectric domain structure by scanning electron microscopy after argon ion milling has been established. Its advantages are exemplified by exposing the domain structure in three widely used ferroelectric ceramics, BaTiO3, (Na,K)NbO3, and Pb(Ti,Zr)O3. Stable high-resolution images revealing domains with widths <30 nm have been obtained. The domain contrast is caused by electron channeling and is strongly dependent on the sample tilt angle. Owing to a strain- and defect-free surface generated by gentle ion milling, pronounced orientation contrast is observed.

Here we look at three types of samples that require a more precise cross sectioning technique than traditional methods: Lithium Ion battery, pharmaceutical tablet, and Zn thin film. For each, scientists need to examine a very thin multilayered “sandwich” of different materials.

Ion Slicer (IS) is an instrument used to prepare TEM lamellas and SEM cross-sections by employing an Ar broad ion beam. The IS has been getting quite popular in TEM and SEM laboratories because of its ease of use and high quality results. However, it is difficult to mill low melting point materials by the Ar broad ion beam because of thermal damage during the milling. Therefore, we have developed a specimen cooling unit for the IS. This cooling unit keeps specimen at low temperature during the ion milling to avoid the thermal damage. We named this system Cryo Ion Slicer(CIS).

Observations from a number of unconventional reservoirs lead us to conclude that four major pore types exist in fine-grained reservoir and non-reservoir rocks, that they are effectively connected, and that pore sizes from nanometers to microns must be considered when evaluating size distributions. This paper uses SEM imaging of Haynesville, Horn River, Barnett and Marcellus Shales to illustrate that pore types other than those hosted by organics are present in unconventional shale gas reservoirs, and that they are continuous and connected to kerogen-hosted pores. In addition, we present evidence that the maximum size of pores originating in organic matter is determined by the size of the kerogen mass (in the case of organic particles) or the geometry of enclosing crystals (in the case of amorphous, pore-filling kerogen). Pairs of secondary and ion-milled backscatter SEM images address the misconception that large pores observed in secondary electron images are grain pullouts.

This study demonstrates that in-situ tensile testing combined with SEM imaging and EBSD mapping enables continuous observation of crystal orientation changes at the microscale.

To better understand the influence of microscale geochemical and microstructural relationships on the bulk petrophysical properties of unconventional shale systems, core samples from four producing North American formations were cross-sectioned with an argon ion polisher and imaged with a field emission scanning electron microscope (FE-SEM) using a variety of complementary detectors. We demonstrate distinct advantages of the ion-polishing technique for the preservation of the internal shale structure. Moreover, we show how such preparation affords a wider choice of imaging options for both chemical and structural characterization, such as backscatter electron observation at varying beam potentials coupled with x-ray and cathodoluminescence spectroscopic techniques.

While the processing range of mechanical polishing is typically 10mm Ø or larger, the sputtering range of conventional planar surface milling is about 5mm Ø. Therefore, there is a growing demand for expanding the sputtering range. However, there are technical challenges associated with expanding this range. In this study, we have explored a new approach to address these challenges.