Quantitative analysis of X-ray absorption spectra using a 2D map representation.

Area of Science:

• Materials Science
• Analytical Chemistry
• Spectroscopy

Background:

• Quantitative analysis of nanosized electrode materials using X-ray absorption near edge structure (XANES) spectra is challenging.
• Understanding structural and electronic variations during ion insertion is crucial for battery material development.

Purpose of the Study:

• To demonstrate a novel 2D map representation technique for quantitative XANES analysis.
• To apply this technique to Li(y)CoO system during the first Li(+) insertion reaction.

Main Methods:

• Utilized a 2D map representation of the first derivatives of absorbance versus Li(+) content and photon energy.
• Analyzed XANES spectra of Li(y)CoO system during Li(+) insertion.
• Identified changes in peak intensities at specific photon energies.

Main Results:

• The 2D map technique successfully quantified spectral variations.
• Peak intensities at 7725 and 7711 eV increased with Li(+) content.
• Largest spectral changes were observed at 1.05 and 1.98 mol of Li content.

Conclusions:

• The developed 2D map approach enables quantitative XANES analysis without conventional simulations.
• This method enhances the confidence in interpreting X-ray absorption spectroscopy (XAS) as a quantitative analytical tool.
• Facilitates detailed characterization of nanosized electrode materials.