FE-SEM

One important sem source that is not based on thermionic emission is the field emission (fe) source. Fe-sem systems typically give images of much higher resolution than conventional sems due to the much narrower energy distribution (on the order of 0.25 eV) of the primary electron beam. A fe source is a pointed W tip from which electrons tunnel under the influence of a large electric field. This different mechanism of electron generation also results in a brightness comparable to a conventional thermionic source with much less current. 

Fig. 2. (a) (b) Transmission electron microscopy (TEM) images of as-grown VGCFs (broken portion) with the PCNT core exposed field emission-type scanning electron microscopy (FE-SEM) image of (c) as-grown and (d) heat-treated VGCFs (broken portion) at 2800°C with PCNT (white line) exposed [20],... 

High catalytic activity and selectivity of silicalite-l/H-ZSM-5 composites must be caused by the direct pore-to-pore connection between H-ZSM-5 and silicalite-l as revealed by Fe-SEM and TEM [43]. The silicalite-l crystals were epitaxially grown on the surface of the H-ZSM-5 crystals. 

The morphology of samples prepared using various surfactants w investigated. Figures 1 and 2 show FE-SEM photographs and X-ray diflfraction patterns of the obtained... 

Fig. 16. Representative FE-SEM images of the branched Pf-BuA-silica hybrid nanoparticles obtained by SCVCP of f-BuA with the inimer 1 at y=6.1 (a, b) and y=l.l(c, d). (Reproduced with permission from [134], Copyright 2001 American Chemical Society.)...

Figure 8.1 FE-SEM images of K-OMS-2 [(a)-(c)], y-Mn02 [(d) and (e)], and Rb-OMS-2 [(f) and (g)] nanomaterials synthesized using the hydrothermal method. Reprinted with permission from [9-11] (2011) American Chemical Society and Wiley-VCH GmbH Co. KGaA.

HRSEM images of STA-7 were taken using a JEOL JSM-7000F (FE SEM). Images of silicalite-2 and zeolite A were taken on a JEOL JSM-7401F (cold-FE SEM) using the Everhart-Thomley (E-T) secondary electron detector. Samples were not coated but placed on a conductive surface. 

Ibidem Observation of zeolite A cold-FE SEM resolving power... 

In the case of zeolite A using a cold-FE SEM all terraces are observable in the HRSEM... 

Figure 3.4 High-resolution FE-SEM and FE-TEM photographs of as-prepared and nanotunneled mesoporousthick H-CNFs (burn-off 32%).

Fig. 5.5 FE-SEM cross-sectional views of tapered nanotubes obtained (a) using the ramp rate 0.43 V/min. to raise the voltage from lOV to 23V within 30 minutes and then holding the voltage at 23 V for 10 minutes and (b) by initially anodizing the sample at lOV for 20 minutes and then increased the voltage linearly at the rate of 1.0 V/min to 23V, and finally kept at 23V for 2 minutes, (c) shows a view of straight nanotubes obtained by applying a constant 23V for 45 minutes. Here, d denotes diameter of apex, and D diameter of cone base.

Fig. 5.21 FE-SEM images of titanium foil sample anodized in DSMO and ethanol mixture solution (1 1) containing 4% HE at -h20 V (vs. Pt) for 70 h at room temperature (a) before and (b) after washing in dilute HE.

Figure 10 FE-SEM images of polyp5rrole/C104 nanotubes obtained by electropolymerization in the pores of supported nanoporous template with thickness of 350 nm (a, b, c) and 1.3 pm (d).

Recent advances in ultra high-resolution low-voltage FE SEM (HR-LVSEM) and extreme FESEM in catalysis... 

The morphology of silver nanopartilces on the cotton surface and paint samples was observed by field emission scanning electron microscopy (FE-SEM JSM-6700F, JEOL, Japan). The size and shape of the nanoparticles in solution were determined with transmission electron microscopy (TEM) (LEO-912-OMEGA, Carl Zeiss, Germany). 

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