Shedding light on electrodeposition dynamics tracked in situ via soft X-ray coherent diffraction imaging

The in situ physicochemical analysis of nanostructured functional materials is crucial for advances in their design and production. X-ray coherent diffraction imaging (CDI) methods have recently demonstrated impressive potential for characterizing such materials with a high spatial resolution and elemental sensitivity; however, moving from the current ex situ static regime to the in situ dynamic one remains a challenge. By combining soft X-ray ptychography and single-shot keyhole CDI, we performed the first in situ spatiotemporal study on an electrodeposition process in a sealed wet environment, employed for the fabrication of oxygen-reduction catalysts, which are key components for alkaline fuel cells and metal-air batteries. The results provide the first experimental demonstration of theoretically predicted Turing-Hopf electrochemical pattern formation resulting from morphochemical coupling, adding a new dimension for the in-depth in situ characterization of electrodeposition processes in space and time.