Operando Characterization of Uranium Dendrite Growth in High-Temperature Molten Salt Electrochemistry by Synchrotron X-Ray Tomography and Diffraction.

In this study, an innovative operando characterization methodology utilizing synchrotron radiation X-ray micro-computed tomography (SR-µCT) and high-energy X-ray diffraction (HEXRD) to investigate dendritic electrodeposition in high-temperature molten salt (HTMS) electrochemistry is presented. This approach enables the in-situ visualization and quantification of uranium dendrite growth and ion diffusion dynamics during the electrochemical reaction of LiCl-KCl-UCl molten salt. Through 3D reconstruction of uranium dendrite imaging and multiphysics simulations of the uranium electrolysis process, the underlying mechanisms of uranium dendrite formation are elucidated. Additionally, in situ HEXRD analysis of electrodeposited uranium reveals that the dendritic growth morphology is intrinsically linked to its crystal structure and orientation. This research not only advances the understanding of uranium dendrite growth and evolution but also establishes a foundational framework for the development of effective dendrite suppression strategies. These findings contribute significantly to the field of HTMS electrochemistry and have potential implications for the design of advanced electrochemical systems.