A Theory-Driven Complementary Interface Effect for Fast-Kinetics and Ultrastable Zn Metal Anodes in Aqueous/Solid Electrolytes

The undesirable side reactions and uncontrolled deposition leads to the electrochemical failure of Zn metal anodes. Herein, driven by theory calculations, a surface texture engineering and passivation layer protection dual-interface strategy is developed. Benefiting from the complementary interface effect, such a dual-interface can realize the integrated regulation of interfacial transport and deposition. That is, inhibiting water-induced side reactions, accelerating the de-solvation of hydrated zinc ions, homogenizing the ion flux, and guiding the Zn(002)-preferred orientation deposition. As a result, such a dual-interface modulated Zn electrode enables a significantly extended stability and a smaller nucleation barrier and polarization effect. Unexpectedly, it can steadily operate for 6600 h at 0.5 mA cm(-2) and 0.5 mA h cm(-2), corresponding to a lifespan >9 months. Highly reversible Zn plating and stripping can be still retained when the current density is improved up to 1, 5, 10, and even 20 mA cm(-2). Beyond that, when it is applied to Zn metal batteries, enhanced rate capability, and cyclic stability can be realized in both aqueous Zn/MnO2 batteries and solid-state Zn/VO2 batteries. This design concept of complementary interface effect is expected to provide a new insight into high reversibility Zn metal anodes.

Automated summary

Driven by theory calculations, a dual-interface strategy of surface texture engineering and passivation layer protection is developed to regulate the undesirable side reactions and deposition behavior of Zn metal anodes. This dual-interface enables the inhibition of side reactions, acceleration of de-solvation, homogenization of ion flux, and guided deposition orientation, resulting in significantly extended stability and improved reversibility of Zn electrodes. It can operate steadily for over 6600 hours and retain high reversibility even at higher current densities. Furthermore, it enhances the rate capability and cyclic stability in both aqueous and solid-state Zn metal batteries.