Accuracy improvement of quantitative analysis for major elements in laser-induced breakdown spectroscopy using single-sample calibration

Accurate determination of major elements using limited standard samples is always a big challenge in laser-induced breakdown spectroscopy (LIBS). Based on a simple calculation process, we propose a new one-point calibration method called single-sample calibration LIBS (SSC-LIBS) to build the calibration and improve the accuracy of determination of major elements. In this work, several major elements (Fe, Cu, Zn, Ni, Cr, Nb, and Mo) in three sets of matrix-matched certified samples were determined without sample preparation. The results showed that compared with multipoint calibration LIBS (MPC-LIBS), the R², RMSECV, and ARE of Cu elements were improved from 0.40 to 0.97, 3.55 wt% to 0.76 wt%, and 5.19% to 1.05%, respectively, while the ARSD decreased from 16.22% to 1.15%. Furthermore, the AREs in the concentration ranges of 1-10, 10-20, 30-40, 50-60, 60-70, and 80-100 wt% were 5.16%, 2.55%, 1.75%, 1.69%, 1.05%, and 0.44%, respectively, with almost all less than 5%, as calculated by SSC-LIBS. These results demonstrated that SSC-LIBS can improve the accuracy and stability of detecting major elements using only one standard sample, which can greatly promote the application of LIBS.