Scanning Electron Microscopy (SEM)

Scanning electron microscopy (SEM) is an electron microscopy technique in which a tiny beam of electrons is scanned across the surface of a sample. A high-resolution 3D image of the sample surface is generated when the electron beam strikes a metal-coated specimen and the electrons reflected (back-scattered) or given-off (secondary electrons) are detected.


Zeiss X 350 SEM (Ultrahigh resolution SEM with field-emission gun)

Hitachi S2600 SEM (Environmental/low vacuum variable pressure SEM)

Tousimis Critical Point Dryer and Cressington Sputter Coater to prepare samples for Zeiss XB350 SEM

Sample Preparation:

Hitachi S2600 – samples are not required to be dehydrated and coated

Zeiss XB350 – samples are required to be dehydrated and coated

  1. Fixation
  2. Dehydration
  3. Critical point dry (complete dehydration)
  4. Mounting
  5. Sputter coating (with Gold and/or Platinum)
  6. SEM

Comparison of XB350 and S2600

Zeiss XB350 Field emission (FE)-SEMHitachi S2600 Variable pressure (VP)-SEM
ResolutionUltrahigh up to 0.7 nmRelatively high up to 5 nm
Electron GunField emission schottky gun
- very bright, tiny spot size, low voltage
Tungsten thermionic gun
- less accurate beam spot
Sample ConditionDry, coated with metalWet sample can be viewed
No sample preparation is needed


Andrew, L. J., Gillman, E. R., Walters, C. M., Lizundia, E., & MacLachlan, M. J. (2023). Multi‐responsive supercapacitors from chiral nematic cellulose nanocrystal‐based activated carbon aerogels. Small, 19(34).

Bi, W., Gyenge, E., & Wilkinson, D. P. (2023). Crossover, volatilization, and adsorption of ammonium ions in a proton-exchange membrane electrolyzer in relation to electrochemical ammonia production. Chemical Engineering Journal, 478, 147359.

Cai, G., Zong, Z., Smith, K. J., & Upham, D. C. (2023). New Molten Metal Catalysts for CO2 and CH4 conversion to 2 : 1 H2 : Co syngas. Chemical Communications, 59(52), 8143–8146.

Fleetwood, S. K., Bell, S., Jetter, R., & Foster, E. J. (2023). Plant-based, aqueous, water-repellent sprays for coating textiles. Soft Matter, 19(36), 7020–7032.