Selected equipment available in the research laboratories of the department of Chemical Engineering

A more detailed information about the equipment is usually given on the pages of the individual research groups

AFM (Atomic Force Microscopy) Dimension Icon (Bruker)

Atomic Force Microscopy (AFM) is a high-resolution scanning probe imaging method. The basic AFM working principle is the measurement of the interaction force between a tip and the sample surface using special probes made by an elastic cantilever (silicon or silicon nitride) with a sharp tip (radius of curvature about 10 nm) on the end. The deflection of the cantilever is measured by laser spot reflected from the cantilever surface into the array of photodiodes. AFM operates in three different modes:

  • Contact mode – for hard samples with flat surface
  • Semi contact (tapping) mode – wide spectra of samples including polymers
  • Non contact mode – soft samples

AFM working principle

 

Generally, the tapping mode is mostly used, because it does not damage the sample surface during the scanning as the contact mode does and with good adjustment the results are without any artifacts in the contrary to the non contact mode. Our AFM is a model Ntegra from NT MDT. The main advantage of AFM in comparison with other techniques:

  • high resolution (almost “atomic”),
  • scanning the samples in their native states (air or liquid environment),
  • 3D sample surface profile,
  • no special sample treatment (i.e., no coating required),
  • good contrast between the individual phases in the multi phase morphology.

 

X-ray micro-tomography

X-ray micro-tomography (micro-CT) is a non-destructive technique which is able to reconstruct the spatial 3D both outer and inner morphology of the scanned sample. The sample is irradiated by X-rays as it rotates from 0° to 360° and the 2D transmission images are taken. From these transmission images the final 3D image of the sample is then mathematically reconstructed. The advantage of this method is that no special sample preparation is required (i.e, no cutting, etching, coating, etc.). The X-ray micro-CT also distinguishes the individual phases in the material on the base of their elementary composition and of the different density of the phases. Our micro CT is Xradia MicroXCT 400 with following parameters:

  • voltage of X ray source: 20 – 90 kV
  • minimum voxel size: 0.2 µm
  • spatial resolution < 1 µm
  • maximum sample weight: 15 kg
  • maximum sample diameter: 50 cm
  • minimum density contrast < 10 %

Xradia MicroXCT 400

JEOL JCM-5700 Scanning Electron Microscope

Despite it’s compact size, JCM-5700 has all the capabilities of a scanning electron microscope. Both in terms of imaging and obtaining micro- and nano-relief surfaces of the sample with magnification in the range from x8 to x300000, and in terms of elemental analysis by energy dispersive X-ray spectrometer.

The software allows to carry out high-precision quantitative measurements on the images, including three-dimensional images obtained using stereo mode.

Technical specifications:

  • Resolution 5 nm
  • Accelerating voltage 0.5 – 20 kV
  • Magnification range x8 – x300000
  • Maximum sample size 150 mm in diameter and 43 mm in height

SKYSCAN MICRO-CT SEM Attachment

SEM JEOL JCM-5700 IS equipped with the SkyScan Micro-CT. This inexpensive attachment adds to any SEM a unique capability to image and measure 2D/ 3D morphometry throughout the entire sample volume, and create realistic visual models for virtual travel within the object.

  • Detail detectability down to 500nm
  • Using SEM electron beam to generate x-rays
  • Possible to work with conductive and non-conductive samples
  • No requirement of any connections to SEM or modifications
  • No ring artifacts in 3D slices due to direct detection camera
  • Supplied with software for 2D/ 3D image analysis and realistic visualization

See manufacturer’s overview of this product for more details.