Mapping of a particular element using an absorption edge with an X-ray fluorescence imaging microscope

Area of Science:

• Materials Science
• Analytical Chemistry
• Physics

Background:

• X-ray fluorescence (XRF) is a powerful technique for elemental analysis.
• High-resolution imaging is crucial for understanding material composition at micro- and nano-scales.
• Existing XRF microscopy methods have limitations in spatial resolution and elemental sensitivity.

Purpose of the Study:

• To develop and characterize a novel X-ray fluorescence imaging microscope.
• To demonstrate the capability of the microscope for two-dimensional element mapping.
• To apply the technique for analyzing complex material samples.

Main Methods:

• Construction of an X-ray fluorescence imaging microscope utilizing a Wolter-type objective mirror (13x magnification).
• Operation at beamline 39XU of SPring-8 using monochromatic X-rays (energy range: 6-10 keV, DeltaE/E ~ 10^-4).
• Employing differential X-ray absorption (using X-rays above and below absorption edges) for elemental contrast.

Main Results:

• Successful construction and characterization of the XRF imaging microscope.
• Achieved two-dimensional element mapping of test specimens, including copper (Cu), cobalt (Co), nickel (Ni), iron (Fe), and titanium (Ti) wires.
• Demonstrated elemental mapping of constituent minerals (Fe, Mn, Ti) within a piemontite-quartz schist rock specimen.

Conclusions:

• The developed XRF imaging microscope provides high-resolution elemental mapping capabilities.
• The technique is effective for analyzing the elemental composition of diverse materials.
• This advancement opens new avenues for materials characterization and geological studies.