Determination of effective atomic numbers and mass attenuation coefficients of samples using in‐situ energy‐dispersive X‐ray fluorescence analysis

The matrix effect has a major impact on energy‐dispersive X‐ray fluorescence analysis (EDXRFA) and is difficult to be evaluated due to that the contents of some low‐atomic‐number elements cannot be identified by in‐situ EDXRFA. Up to today, the fundamental parameter algorithm proposed by Rousseau has been widely applied to correct the matrix effect. Accordingly, determining the matrix and mass attenuation coefficient (μ/ρ) of sample is a key issue for the fundamental parameter algorithm. In present work, the method to deduce μ/ρ by effective atomic number (Z_eff) was studied. First, the relationship between Z_eff and coherence to Compton scatting ratio (R) of the incident X‐ray was determined by standard samples. Then, we deduce Z_eff and their μ/ρ. The value of μ/ρ deduced by our method is in good agreement with that calculated by WinXCOM, and the relative change (Δ) is less than 7%. We also deduced Z_eff and their μ/ρ of Chinese national standard soil samples employing our method and good agreement with the calculated values were also obtained. We found that the agreement between experimental values of μ/ρ with theoretical values by WinXCOM still exists when the energy of the incident X‐ray is greater than 4 keV, and the Δ is less than 10%. The result indicates that our method may be applied directly to in‐situ EDXRFA.