Microscopic Fingerprints of Electrodeposited Zinc Morphologies Encoded inside Electrode Surface Signature

The evolution of a metal surface during electroplating is a key phenomenon with implications for materials and coatings engineering, as well as for metal–air batteries used in energy storage. The formation of specific surface morphologies─mossy, compact, or dendritic─arises from complex physical processes. These morphologies are typically analyzed ex situ through postmortem characterization, as operando observations remain highly challenging. Dendritic growth under fast charging conditions represents a major limitation for metal-based batteries. In this work, we combine a theoretical analysis of the electrochemical response of zinc electrode surfaces─modeled at low overpotential as a stack of microscopic oxide layers─with in operando electrochemical scanning experiments using linear sweep voltammetry (LSV). This approach reveals distinct signatures for each morphology within a parametric phase diagram, as well as characteristic microscopic fingerprints reflecting morphological growth dynamics. Such analysis enables in operando electrochemical evaluation of both the microscopic state and the growth dynamics of the electrode surface. In this context, in situ refers to probing performed directly within the cell, without electrode removal or reconditioning, rather than to imaging-based characterization. These findings pave the way for more precise microscopic control of metal deposition.