Three-dimensional imaging of chemical phase transformations at the nanoscale with full-field transmission X-ray microscopy

TLDR

Imaging morphology and phase distribution across multiple length scales reveals how nano‑ and micrometer‑scale factors drive macroscopic behavior, yet conventional electron‑ and X‑ray‑based techniques combined with spectroscopy are limited by too small fields of view to represent composite samples. The study proposes a new X‑ray imaging setup that combines full‑field transmission X‑ray microscopy with XANES spectroscopy to track two‑ and three‑dimensional morphological and chemical changes in large volumes at nanometer resolution. The method integrates full‑field TXM and XANES spectroscopy, enabling nanoscale chemical speciation in thick samples (>20 µm) while covering large volumes with high spatial resolution. The combined TXM‑XANES approach delivers nanoscale chemical speciation in thick (>20 µm) samples with minimal preparation, achieves high throughput for large‑area analysis within minutes to hours, and is demonstrated on battery electrodes, indicating broad applicability.

Abstract

The ability to probe morphology and phase distribution in complex systems at multiple length scales unravels the interplay of nano- and micrometer-scale factors at the origin of macroscopic behavior. While different electron- and X-ray-based imaging techniques can be combined with spectroscopy at high resolutions, owing to experimental time limitations the resulting fields of view are too small to be representative of a composite sample. Here a new X-ray imaging set-up is proposed, combining full-field transmission X-ray microscopy (TXM) with X-ray absorption near-edge structure (XANES) spectroscopy to follow two-dimensional and three-dimensional morphological and chemical changes in large volumes at high resolution (tens of nanometers). TXM XANES imaging offers chemical speciation at the nanoscale in thick samples (>20 µm) with minimal preparation requirements. Further, its high throughput allows the analysis of large areas (up to millimeters) in minutes to a few hours. Proof of concept is provided using battery electrodes, although its versatility will lead to impact in a number of diverse research fields.