Fluorine analysis using Laser Induced Breakdown Spectroscopy (LIBS)

Abstract

Laser induced breakdown spectroscopy (LIBS) is evaluated for detecting fluorine using a commercially available J200 Tandem LA/LIBS system from Applied Spectra, Inc. The 685.6 nm fluorine atomic emission line was used to detect and determine the best calibration method for quantifying the amount of fluorine in a set of prepared NIST SRM 120c phosphate rock standards. The multivariate calibration model, based on partial least squares regression (PLS), provided the best accuracy and precision for the sample set analyzed in this study. The detection limit of fluorine using the J200 LIBS system with a 213 nm laser and an ICCD was determined to be 135 ppm from a phosphate rock standard. A rare earth element (REE)-rich mineral high in fluorine content was used to access the potential applications of mapping the fluorine content over a 16 mm2 surface area of the sample.