Determination of potassium in ceramic raw materials using laser-induced breakdown spectroscopy combined with profile fitting

The determination of potassium (K) content in ceramic raw materials provides important references for ceramic sintering. To realize rapid, in situ, and real-time analysis detection, a laser-induced breakdown spectroscopy (LIBS) system was set up to analyze K content in ceramic raw materials. However, the self-absorption was the serious influence on the accuracy of K element analysis. In this work, a method of profile fitting with Lorentz function was proposed to reduce the self-absorption effect in LIBS. After Lorentz fitting, the determination coefficient (R² factor) for K element improved from 0.993 to 0.998, the root mean square error of cross-validation reduced from 0.458 wt. % to 0.145 wt. %, and the average relative error reduced from 13.769% to 5.121%. The results indicate that the Lorentz fitting can effectively reduce the self-absorption effect, and improve the accuracy of quantitative analysis for K element. According to the results, the proposed approach can be a promising method for determination of elements that suffer from self-absorption in LIBS.