Dual-function protective layer for highly reversible Zn anode

The thermodynamic instability of zinc anodes in aqueous electrolytes leads to issues such as corrosion, hydrogen evolution reactions (HER), and dendrite growth, severely hindering the practical application of zinc-based aqueous energy storage devices. To address these challenges, this work proposes a dual-function zinc anode protective layer, composed of Zn-Al-In layered double oxides (ILDO) by rationally designing Zn-Al layered double hydroxides (Zn-Al LDHs) for the first time. Differing from previous works on the LDHs coatings, firstly, the ILDO layer accelerates zinc-ion desolvation and also captures and anchors SO42−. Secondly, the in-situ formation of the Zn-In alloy phase effectively lowers the nucleation energy barrier, thereby regulating zinc nucleation. Consequently, the zinc anode with the ILDO protective layer demonstrates long-term stability exceeding 1900 h and low voltage hysteresis of 7.5 mV at 0.5 mA cm−2 and 0.5 mA h cm−2. Additionally, it significantly enhances the rate capability and cycling performance of Zn@ILDO//MnO2 full batteries and Zn@ILDO//activated carbon zinc-ion hybrid capacitors. This simple and effective dual-function protective layer strategy offers a promising approach for achieving high-performance zinc-ion batteries.