What do you want to compare? What characterisation have you done? Do you mean elemental characterisation like EDX? or EELS? or crystallographic information from SAED? Or do you mean grainsize analysis? How big (roughly) are your particles? If they are small (e.g. < 50 nm) TEM might be more reliable than SEM imaging as TEM tends to have higher resolution. Is it shape analysis? as TEM only provides a projection of the shape of the particle, whereas SEM will give you more 3D information on particle morphology.
What do you want to compare? What characterisation have you done? Do you mean elemental characterisation like EDX? or EELS? or crystallographic information from SAED? Or do you mean grainsize analysis? How big (roughly) are your particles? If they are small (e.g. < 50 nm) TEM might be more reliable than SEM imaging as TEM tends to have higher resolution. Is it shape analysis? as TEM only provides a projection of the shape of the particle, whereas SEM will give you more 3D information on particle morphology.
True Volker, if you're lucky enough to have the software and set up for tomography :-)
Dear, Yogesh
Can you put some more details ..
Is SnO2 is the single pure material which you are able to see, or SnO2 present as a particle in the different matrix.
whether SnO2 is in the crystalline phase or in amorphous structure.
suppose, SnO2 is single phase structure which you are characterize through SEM. If it is in the crystalline form then you are able to see the grains, if the grains are in the micron size. "If some other phase is present in your SnO2 matrix you can easily revealed through the BSE mode in SEM. contrast depending on the atomic number".
If it is in the particle form, which is present in the matrix then you can able to see its morphology.
Now come to TEM part ... as you already aware that ... TEM can be use for variety of purpose..... like if you want to know the grain orientation relation ship you can use TEM.
The crystalline or amorphous behaviour of your material can be confirm by the TEM SADpattern.
The dark field mode can be useful to revealed the defects as well as fine particles present in your material.... with additional to that, the alpha and beta tilt can be very useful to revealed the clear mechanism of your material microstructure. In SEM you can able to see only grain but here you can even see the grain boundary and able to tell the defect present in the grain boundary .....
One needs to do both SEM and TEM repeatedly, on several different batches from the SAME SAMPLE in order to increase the confidence level of the extrapolated structural, compositional and morphological data.
Volker, actually it is very easy and relatively cheap to get 3D data from SEM. 3D images, 3D reconstructions, profiles, height measufrements…
SEM : u can determine the overall morphology, like porosity, fluffiness....etc
TEM: u can determine the size and shape of the microcrystallites
To what is mentioned above I can add that HR-TEM can be helpful in figuring out crystalline domains and atomic-scale structure revealed by lattice fringes.
Results obtained from a specimen under TEM can not be comparable with those from SEM. Obviously, SEM provides 3D information from surfaces of thick specimens while TEM gives 2D information from 50 to 100 nm thick (ultrathin) sections.
Hi,
Electron microscope follows the same ideas of optical microscope, but uses electrons instead of light;“Lens” here are not the optical materials (like glass), but electrical field.
A Scanning Electron Microscope uses a beam of electrons to scan the surface of an object to create an image detailing the topography and composition of the object’s surface.
A Transmission Electron Microscope is used to magnify objects. It aims a beam of electrons onto the object to form a magnified image called a micrograph.
In SEM an electron beam is focused into a small probe and is rastered across the surface of a specimen.Several interactions with the sample that result in the emission of electrons or photons occur as the electrons penetrate the surface.These emitted particles can be collected with the appropriate detector to yield valuable information about the material.The most immediate result of observation in the scanning electron microscope is that it displays the shape of the sample.The resolution is determined by beam diameter.
In transmission electron microscopy (TEM), a beam of highly focused electrons are directed toward a thinned sample (
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