|
SUBSTRATES FOR HIGH-RESOLUTION IMAGING
We recommend the following TEM Window grids for high-resolution imaging of nanoparticles or nanotubes:
-
NANOPOROUS Pure Silicon TEMwindows have 10-60 nm diameter nanopores on which nanoscale materials may be suspended for truly background-free imaging
- 5 or 10 nm Silicon Nitride TEM windows are perfectly flat and robust enough for most sample preparation procedures
GRAPHENE GRAIN IMAGING
A beautiful patchwork of graphene grains was imaged and
published in Nature last month by researchers at Cornell University. Huang et
al used TEM and diffraction-filtered imaging to show the location, orientation
and boundaries of hundreds of graphene grains. Their work confirmed that grain
boundaries weaken the mechanical strength of graphene, but do not significantly
alter the electrical properties.
Below you will see a false-color, composite dark-field TEM image of graphene grains. In this image, each color represents graphene of a different crystallographic orientation. These images were acquired through 10 nm Silicon Nitride windows and were taken by Pinshane Huang at Cornell University.
Huang's original work was performed with microporous TEM
films where post-imaging background substraction was performed. Current work
and future studies are being conducted at Cornell using TEMwindows' robust and
ultrathin 10 nm silicon nitride, which provides an excellent background-free
imaging substate.
Bright patches indicate graphene grains of a ~10 range of crystallographic orientations. On the left, getting a complete picture of the graphene grain structure is difficult because the thick membrane obstructs much of the lattice. Moving to thin windows (on the right), we can get comparable contrast while viewing larger continuous areas. The particles on the right image are from a dirty graphene sample, not the grid. Scale bars are 2 microns.
Pinshane Huang, PhD Candidate
Muller Group, Cornell University
FEATURED TEM WINDOWS:
|
