Development of High-Energy µ-X-ray Fluorescence and X-ray Absorption Fine Structure for the Distribution and Speciation of Rare Earth Elements in Natural Samples

Micro-X-ray fluorescence and X-ray absorption fine structure (µ-XRF-XAFS) is one of the most powerful tools to identify distribution speciation trace elements in natural samples with µm spatial resolution. However, conventional µ-XRF-XAFS studies applied rare earth (REEs: lanthanide + Y this study) are mainly limited their L-edges L lines (except for Y) that subject strong interferences from other (mainly transition metals). In study, we extend higher energy region (HE-µ-XRF-XAFS) by using an incident microbeam (size: ca. 1 × µm2) between 38 54 keV realize K-edge excitation analysis without at BL37XU beamline, SPring-8 (Japan). This method enables us simultaneously analyze (i) REE patterns (from La Dy), (ii) XAFS spectra, (iii) µm-scale each sample. The proposed also realizes simultaneous application µ-XAFS low (e.g., Fe K-edge) high (lanthanide K-edges) same spot changing setup system detuning technique.