Design principles of underpotential deposition chemistry for highly reversible multivalent metal anodes

Aqueous multivalent metal batteries have high theoretical capacities and are cost-effective; however, the low electrochemical reversibility caused by the notorious parasitic reactions of metal anodes hinders their practical application. In this study, an underpotential deposition (UPD) strategy for designing heterogeneous metal substrates to regulate the multivalent metal plating/stripping behavior was developed. Using Al as a model system, a theory-to-application metric to screen proper heterogeneous metal was established through the theoretical and experimental evaluation of eight common metals according to their thermodynamics stability and kinetics aluminophilicity. Specifically, Sn metal has a strong binding affinity for Al3+ ions and can effectively alleviate the hydrogen evolution reaction, thus enabling highly reversible underpotential Al plating/stripping for over 2800 h at 1 mA cm-2, considerably longer than that of Al metal. Furthermore, the UPD strategy could be extended to other multivalent metals, including divalent Mg and Sn and trivalent In. This study provided an effective strategy for improving the reversibility of metal plating/stripping and constructing high-stability multivalent metal batteries.