Application of improved matrix dilution method in quantitative analysis of Ni-Co-Mn ternary precursor

Abstract When using energy-dispersive X-ray fluorescence (EDXRF) to analyze Ni-Co-Mn (NCM) samples, if the standard sample's concentration greatly differs from the unknown sample's concentration, the traditional matrix dilution method requires repeated dilution and measurement. This makes the process time-consuming and labor-intensive. This study proposes an improved matrix dilution method to reduce sample preparation and analysis. This method first establishes a functional relationship model between the dilution factor and the characteristic X-ray intensity. Then the characteristic X-ray intensity of the analyzed element can be calculated by this model, avoiding unnecessary dilution and measurement steps. To verify the effectiveness of this method, the dilution factors and characteristic X-ray intensities of the test samples were fitted using the established functional relationship. The fitting results showed that the fitting coefficients of determination of the Mn, Co, and Ni were all 0.999. Quantitative analysis was performed on the characteristic X-ray intensity fitting values and measured values of the test samples. The results showed that the quantitative results of the two were consistent. The average error of the three elements for both methods was 1.1% and 0.7%, respectively. It shows that through the established functional relationship, the characteristic X-ray intensity can be effectively calculated by the dilution factor. This method can be applied to samples with identical elements and proportions of target elements, but with different concentrations, using the same set of standard samples.