Spatially Resolved Elemental Analysis, Spectroscopy and Diffraction at the GSECARS Sector at the Advanced Photon...

Area of Science:

• Environmental biogeochemistry
• Synchrotron-based materials analysis
• Advanced X-ray imaging techniques

Background:

• High-brightness synchrotron facilities are crucial for environmental biogeochemistry research.
• X-ray microprobes (XRM) are powerful tools for elemental and structural analysis.
• Recent upgrades to the XRM at the Advanced Photon Source (APS) have enhanced its capabilities.

Purpose of the Study:

• To describe the improved XRM instrumentation and techniques at APS.
• To demonstrate the XRM's capabilities in elemental imaging and speciation.
• To highlight the advantages of XRM for environmental and biogeochemical research.

Main Methods:

• Utilizing a canted undulator geometry upgrade for increased beam time and extended energy range (down to sulfur K edge).
• Employing rapid, high-resolution elemental imaging, including fluorescence microtomography.
• Applying microscale X-ray absorption fine structure spectroscopy and microscale X-ray diffraction.

Main Results:

• Achieved rapid, high-resolution 2D elemental mapping of large samples.
• Enabled 3D imaging of internal elemental distributions in fragile hydrated specimens without physical slicing.
• Facilitated spatially resolved speciation determinations of contaminants and identification of host phases.

Conclusions:

• The upgraded XRM at APS significantly enhances capabilities for environmental biogeochemistry research.
• The instrument is advantageous for detailed elemental and speciation analysis of complex environmental samples.
• Further improvements are anticipated with proposed upgrades to the APS.