Mapping analysis of heavy metal elements in polluted soils using Laser Induced Breakdown Spectroscopy

In this work, LIBS was applied to analyze the spatial concentration distribution of toxic heavy metals in soils around a smelter. The spectral lines of copper, lead and chromium were used to directly analyzed the concentration distribution in soils around the smelter.

The relevance between the spectral line intensities of Cr and the total concentrations detected by inductively coupled plasma optical emission spectrometry was poor. To improve the analysis accuracy, the calibration-free LIBS method combined with Saha equation was used. Compared with the preliminary analysis result of spectral line intensities, the concentration ratios of Cr/Si obtained from CF-LIBS showed a good correlation with the total concentrations.