HRSEM microscopy

Characterization Surface area of porous electrodes can be calculated from gas -> adsorption, using appropriate models (e.g., the commonly used B.E.T model). The electrode structure can be analyzed by X-ray and neutron diffraction. The pore morphology can be analyzed by electron microscopy (SEM, TEM, HRTEM, and HRSEM). 

Electron microscopy was used to provide more details on the nature of the coke deposits as well as their location. HRSEM reveals the HS-FER crystallites to be platelets, typically 250 nm in size, with a mean thickness of only 20 nm. For a spent HS-FER containing 9.1 %w of coke TEM photographs are displayed in Fig. 7. Careful inspection of the FER platelets reveals that they are bordered by a layer of amorphous material (labelled) which is probably coke. Also at the edge of the platelets there are layers of similar width (picture corresponds to a view down the (100) surfaces as determined by a selected area diffraction study). This suggests that all the external surfaces, both porous and non-porous, contain a layer of coke. To confirm that the amorphous layers indeed consist of carbonaceous material, PEELS spectra were collected which closely resemble that of the amorphous carbon film supporting the sample crystallites. With samples containing less carbon (below 7 %w), TEM does not reveal a coke layer at the surface of the crystallites, but rather reveals discrete coke clusters of 1.0-1.5 run. 

Analysis methods, used for the investigation of modified surfaces and interfaces, are briefiy reviewed. Emphasis is on the combination of chemical, structural/ morphological, electronic, and optical characterization. Many techniques such as transmission electron microscopy (TEM), standard X-ray photoelectron spectroscopy (XPS) using A1 or Mg K radiation, high-resolution scanning electron microscopy (HRSEM), and standard scanning probe microscopies (AEM in contact... 

High-iesolution scanning and transmission electron microscopy (HRSEM, HRTEM) can provide very specific information about surface films on any kind of particles. A comparison between pristine particles and particles scraped from cycled electrodes can provide very comprehensive information. Using element analysis, STEM techniques, and selected area electron diffraction (SAED), it is possible to map surface species in a nanometric scale [30]. 

Crack tip opening displacement (CTOD) measurements are complex to undertake due to the need to perform high-resolution scarming electron microscopy (HRSEM). 

HRSEM High-resolution scanning electron microscopy... 

Scanning electron microscopy (SEM) and high-resolution SEM (HRSEM) (Goodhew et al. 2001) have been extensively used to study the morphology of porous silicon. It is virtually impossible to provide the reader with a complete list of works in this field. In this regard, many SEM images of high quality can be found in books, reviews (see, e.g., Canham 1997 Lehmann 2002 Sailor 2011), and even the Web ... 

Topography The surface topography of the films was analysed by (a) atomic force microscopy (AFM Nanoscope IIIA Multimode SPM, Veeco Instmments) in tapping mode under ambient conditions (cantilever resonant frequencies were in the range 330-350 kHz and the force constant was 42 N/m) and (b) high-resolution scanning electron microscopy (HRSEM FEI, NovaNano SEM 230). 

---