Microscopy
Materials scientists study the properties of materials and how materials interact
with one another at the molecular level. A lot of research takes place at the nanometer scale so it becomes necessary to have sophisticated
microscopes to visualize what is taking place at such dimensions. Below is an Atomic
Force Microscope (AFM) and the images it can generate. Material scientists work with
many kinds of microscopes. An AFM is very helpful in showing the 3-D surface of a
specimen at a very high magnification.
Left: A view of the probe whose tip actually scans the surface
of the specimen back and forth producing high resolution images. Right: Placing the
specimen on the AFM.
Above are nanoparticles of silica captured by the AFM. Notice the scale in nanometers.
Below are nanocylinders which were structured by combining synthetic polymers with
ceramic components. (See Wiesner Research). Notice
that the scale is in microns .
This
is a picture of Phong Bort Du, graduate student in the Department of Materials Science
and Engineering at Cornell University, getting the specimen ready to be looked at
under the AFM. Before materials are examined, careful preparation of the specimen
must take place. In many cases, choosing the correct specimen holder becomes very
important when trying to view the specimen from various angles.
Below are pictures of nanostructures also created by synthetic polymers that were
combined with ceramic components (see Wiesner Research).
These were taken with a Transmission Electron Microscope (TEM). The images in a TEM
are actually created by the scattering of electrons given off by the specimen when
hit by a radiation source within the TEM. Those electrons which are emitted are then
captured and translated into very precise visual images.
Nanocylinders - TEM (Trasmission Electron Microscope)
Nanospheres -TEM (Transmission Electron Microscope)
All pictures courtesy of the Wiesner Group
at Cornell University.
Click below on these links to learn more about the types of microscopes being
used in the field of Materials Science and Engineering and how they work. It's fascinating
to see the molecular structure of materials!