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Inhibition effects of an γ-(2,3-epoxypropoxy) propyl-trimethoxy-silane (abbreviated as epoxy-silane) and 3,6-Dioxa-1,8-octanedithiol (abbreviated as DOT) film on copper corrosion in 3.5 wt% NaCl solution were studied by digital hsolography, electrochemical methods and surface characterization approaches. In-situ observation of the concentration change at the electrode/electrolyte interface during dynamic potential scan by holography revealed that the dissolution of copper was inhibited significantly and no CuCl film formation was found on the surface of the modified film. Sputtering measurements by X-ray photoelectron spectroscopy showed that some Cl− ions permeated into the outer layer of the epoxy-silane/DOT film and formed CuCl interlayer with the Cu+ ions in the film. The CuCl interlayer in the modified film blocked its micropores, inhibiting the copper corrosion. The initial electro-dissolution reactions on bare copper and modified copper have been discussed accordingly. The study proved the digital holography to be an effective method to evaluate anti-corrosion performance and elucidate the related mechanisms in particularly.

Aqueous zinc-ion batteries (ZIBs) are regarded as one of the most promising electrical energy-storage systems for their eco-friendliness, low cost and high-safety. Although there have been a lot of studies recently on the Zn metal anode, little attention has been paid to its initial nucleation and growth behavior, which is critical to the understanding of fundamental mechanisms of the Zn plating. Herein, the digital holographic surface imaging (DHSI) method, combined synchronously with electrochemical tests, is employed to in-situ observe the non-uniform concentration changes on the surface of the copper substrate caused by the Zn nucleation and growth at the early stage. It is the first time to observe the early uneven depositions from a perspective of solution concentration changes in a symmetrical battery system. Results show that the later dendritic growth of Zn is closely related to the nucleation and earlier deposition process. Based on the phase maps obtained with in-situ DHSI technique, the nucleation and growth during the Zn electrodeposition can be closely investigated and vividly demonstrated, offering a promising avenue towards the understanding of the interfacial electrochemistry in all aqueous metal-ion batteries.