Energy-Dispersive X-Ray Fluorescence Determination of Pure- Element Intensities Using the "Low-Concentration Method"

Abstract

A new relation between ln(fluorescent intensity ratio of analyte to pure analyte/concentration of analyte) and ln(fluorescent energy) can be expressed as ln(I_i/(Iⁱ_oc_i))=aln(E)+b, where a and b are constants. This relation depends on the pure-element intensity (I^o_i). Although the simplest way to obtain pure-element intensities is to use thick pure-metal foils, there are, however, many elements whose pure-metal foils are not available. This paper proposes a new method for determining pure-element intensities, which we shall call the "Low-Concentration Method". Essentially, by measuring the intensities of known low concentrations of elements in a known matrix and calculating the appropriate alpha coefficients from tabulated mass-absorption coefficients, the pure-element intensities can be obtained. It was found that such values are in good agreement with those obtained using thick metal foils as well as with those using oxides.