1. Transmission Electron Microscopy
Peter Harris

2. Transmission electron microscopy
► What is transmission electron microscopy?
► TEM in biological science
► TEM in physical science
► CfAM’s TEMs
► Recent developments in TEM

3. SEM & TEM Scanning electron microscope
Specimen
Condenser lens
Objective lens
Specimen
Projector lens
Fluorescent screen
Electron gun
Digital camera
Electron gun
Electron gun
Electron gun
Condenser lens
Objective lens
Specimen
Projector lens
Fluorescent screen
Digital camera
Scanning electron microscope
Transmission electron microscope

4. Transmission electron microscopy
Electron gun
Current passed through LaB6 crystal causes electrons to be emitted. Anode accelerates electrons to 80 kV – 200kV.
Electromagnetic lenses
A current through the coils creates a magnetic field, symbolized by red lines in the diagram on the left. Electrons close to the centre are less strongly deflected than those passing through the lens far from the axis.

5. Transmission electron microscopy
Specimens for TEM
3 mm TEM grid
Carbon films

6. Contrast in the TEM - 1 Biological and “soft matter”
Absorption contrast:
Heavy atoms absorb more electrons than light atoms.
Scattering contrast:
Some electrons blocked by objective aperture.

7. Positive staining
Electron-dense heavy metal salt selectively stains certain features within the sample.
Block copolymer containing polystyrene and polymethylmethacrylate stained with ruthenium tetroxide.

8. Biological TEM - negative staining
Surrounding biomolecules with thin amorphous layer of heavy metal salt. Reveals structure, and reduces structural flattening that occurs in the absence of stain.
Adenovirus negatively stained with uranyl acetate
Commonly used stains: uranyl acetate, uranyl formate, sodium/potassium phosphotungstate, ammonium molybdate.

9. Biological TEM - negative staining
Peptide fibrils, stained with methylamine tungstate (1%) on formvar/carbon grids.
Marta Krysmann, School of Chemistry

10. Biological TEM – preparing specimens from tissue
Fix  dehydrate  set in resin  section  deposit on grids  stain
Microtome

11. Biological TEM – thin section
Kidney

12. The transmission electron microscope is not just a microscope!
Diffraction pattern (crystalline C60)
Energy dispersive X-ray spectrum
X-ray analysis workshop: November 27 

13. Contrast in the TEM - 2
Diffraction contrast

14. Transmission electron microscopy
TEM in physical science – bright field imaging
Platinum/alumina catalyst
Dislocations in stainless steel foil

15. Contrast in the TEM - 3
Phase contrast: lattice imaging

16. Multiple electron scattering
Electrons passing through a crystal are multiply scattered

17. Image simulations
Example of image simulation: amphibole crystal

18. EM Lab’s TEMs FEI/Philips CM20 Analytical TEM
JEOL 2010 High resolution TEM

19. New developments in TEM - 1
Ultra-high resolution TEM, with aberration correction, Tsukuba, Japan.

20. New developments in TEM - 2
Tomography – bringing the 3rd dimension to TEM

21. TEM at CfAM
Carbon nanostructures

22. TEM at CfAM Nanoporous Pt particles - applications in catalysis.
Samina Akbar& Joanne Elliott,
Department of Chemistry

23. TEM at CfAM
Micro-phase separated polymer particle, 120nm diameter. Hamley group.

24. Becoming an EMLab user
Sherrie Foo

25. Remaining workshops Environmental & Cryo SEM 20 November 2013
Date
Topic
20 November 2013
Environmental & Cryo SEM
27 November 2013
X-ray Analysis and Elemental Mapping

26. Transmission electron microscopy
► Questions?
► Demo