Demonstration of an AI-driven workflow for dynamic x-ray spectroscopy
This work improves data collection efficiency for XANES experiments in materials science, enabling better time resolution for tracking chemical changes in applications like battery materials and catalysts, though it is incremental as it builds on existing adaptive sampling methods.
The paper tackled the problem of time-consuming XANES spectroscopy data collection by developing a knowledge-injected Bayesian optimization approach, which accurately reconstructs spectra using only 15-20% of typical measurement points while maintaining errors as low as 0.03 eV for peak energy and 0.005 RMSE.
X-ray absorption near edge structure (XANES) spectroscopy is a powerful technique for characterizing the chemical state and symmetry of individual elements within materials, but requires collecting data at many energy points which can be time-consuming. While adaptive sampling methods exist for efficiently collecting spectroscopic data, they often lack domain-specific knowledge about XANES spectra structure. Here we demonstrate a knowledge-injected Bayesian optimization approach for adaptive XANES data collection that incorporates understanding of spectral features like absorption edges and pre-edge peaks. We show this method accurately reconstructs the absorption edge of XANES spectra using only 15-20% of the measurement points typically needed for conventional sampling, while maintaining the ability to determine the x-ray energy of the sharp peak after absorption edge with errors less than 0.03 eV, the absorption edge with errors less than 0.1 eV; and overall root-mean-square errors less than 0.005 compared to compared to traditionally sampled spectra. Our experiments on battery materials and catalysts demonstrate the method's effectiveness for both static and dynamic XANES measurements, improving data collection efficiency and enabling better time resolution for tracking chemical changes. This approach advances the degree of automation in XANES experiments reducing the common errors of under- or over-sampling points in near the absorption edge and enabling dynamic experiments that require high temporal resolution or limited measurement time.