We Measure Particle Size, Perform Catalyst Size Analysis, and More
When crystalline domains are less than 200 nm in size, appreciable broadening in the X-ray diffraction lines will occur. These domains may in fact be related to the particle size and correspond to the particle size measured by other techniques. At other times, however, these domains may lie within the larger particle and may be an important and distinguishing feature. A classic example of this is subgrains formed by dislocation walls within metallic grains.
Broadening of the diffraction lines can be used to estimate the domain size by several different X-ray diffraction techniques. In the simplest case where the domains are stress free, the size can be estimated from a single diffraction peak. But in those cases where stress may be present, a more robust method is required such as the Warren-Averbach or Rietveld methods that utilize several diffraction peaks.
Among the many uses of this method are:
- Catalyst size analysis
- Studies of precipitation processes
- Nanoscale composites
- Phase transformation kinetics
- Fibers and composites
- Quality control
- Forensic analysis