Construction of Zn Sn interface layer on Zn anode surface by annealing method for reversible zinc-ion batteries

Despite their promising potential, aqueous zinc-ion batteries (AZIBs) suffer from detrimental parasitic reactions during operation, including uncontrolled dendrite growth, hydrogen evolution reaction (HER), and corrosion-induced passivation. Therefore, to address these challenges, we propose the modifying zinc anodes by integrating zinc-friendly metal coatings. Specifically, Zn Sn interface layer was successfully fabricated on a zinc substrate by a facile chemical deposition method. The subsequent thermal annealing process causes a crystalline rearrangement of the Sn structure, realizing a dual functional enhancement. Finally, the formation of dense Sn layers eliminates residual stresses. More importantly, it generates an abundance of electrically active sites for uniform Zn 2+ deposition, suppressing HER and mitigating the corrosion. Notably, the Sn (200) crystallographic plane with the elevated surface energy shows an excellent ability to inhibit Zn 2+ aggregation, facilitating highly reversible zinc plating/stripping kinetics. The optimized Zn Sn composite anode exhibits a remarkable cycling stability, maintaining a stable operation for over 2000 h at 1 mA cm −2 , 1 mAh cm −2 with minimal voltage polarization. Furthermore, it achieves exceptional coulombic efficiency (99.57%) throughout 1000 cycles. This study highlights the significance of constructing the thermodynamically stable zincophilic substrates through simple and effective interface engineering strategies, providing valuable insights for advancing next-generation aqueous battery technologies.