Accuracy improvement of single-sample calibration laser-induced breakdown spectroscopy with self-absorption...

Area of Science:

• Analytical Chemistry
• Spectroscopy
• Materials Science

Background:

• Single Sample Calibration Laser-Induced Breakdown Spectroscopy (SSC-LIBS) is valuable for elemental analysis when standard samples are scarce.
• The self-absorption effect in plasma plasma significantly compromises the accuracy of traditional SSC-LIBS by disrupting the spectral intensity-concentration relationship.
• This limitation hinders the precise quantitative analysis capabilities of SSC-LIBS in critical applications.

Purpose of the Study:

• To develop and validate an improved SSC-LIBS method incorporating self-absorption correction (SSC-LIBS with SAC).
• To enhance the quantitative accuracy of SSC-LIBS without requiring complex sample preparation or extensive calibration data.
• To broaden the applicability of SSC-LIBS in fields like space exploration, geology, archaeology, and jewelry identification.

Main Methods:

• An improved SSC-LIBS technique was developed, integrating a self-absorption correction (SAC) module.
• The method utilizes the relative self-absorption coefficient (K) to correct spectral line intensity ratios.
• Validation was performed using alloy and pressed ore samples to assess quantitative performance.

Main Results:

• The SSC-LIBS with SAC method demonstrated a substantial reduction in Root Mean Square Error of Prediction (RMSEP) and Average Relative Error (ARE) for both alloy and ore samples.
• For alloy samples, average RMSEP decreased from 0.83 wt.% to 0.40 wt.%, and average ARE from 13.75% to 4.06%.
• For pressed ore samples, average RMSEP decreased from 4.77 wt.% to 2.34 wt.%, and average ARE from 90.48% to 14.60%.

Conclusions:

• The proposed SSC-LIBS with SAC method significantly enhances quantitative accuracy compared to traditional SSC-LIBS.
• The technique offers improved universality and applicability across diverse sample types, including those lacking standard reference materials.
• This advancement represents a major step towards the widespread adoption of accurate SSC-LIBS for elemental analysis in challenging environments.