Spatially offset Raman scattering line-mapping as a potential tool for particle size analysis.

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Materials Science

Background:

• Particle size significantly influences material properties and behavior.
• Accurate particle size measurement is crucial in various industrial applications.
• Spacially offset Raman spectroscopy (SORS) offers a non-destructive analytical technique.

Purpose of the Study:

• To investigate a SORS line-mapping scheme for particle size measurement.
• To correlate photon migration patterns with particle size in powder samples.
• To evaluate the potential of SORS for quantitative particle size analysis.

Main Methods:

• Developed and applied a SORS line-mapping technique.
• Measured photon migration by analyzing peak intensity decay with offset distance.
• Utilized low-density polyethylene (LDPE) and middle-density PE (MDPE) powders of varying particle sizes.
• Analyzed the slope of intensity decrease to infer photon distribution and particle size.

Main Results:

• Photon migration varied with particle size, affecting reduced scattering coefficients.
• A steeper intensity decrease slope correlated with smaller particle sizes and narrower photon distributions.
• Higher particle density (MDPE) resulted in narrower photon distributions and steeper slopes compared to lower density (LDPE).
• The SORS scheme demonstrated sensitivity to particle size variations.

Conclusions:

• The SORS line-mapping scheme shows potential for non-destructive particle size measurement.
• Particle size can be determined by analyzing the slope of intensity decay in SORS mapping.
• The method may be extendable to other powder samples with calibration.
• SORS provides valuable information for both particle size analysis and chemical composition.