Hygroscopic Organic Complex Mutated Helmholtz Plane of Zn Anode for Outstanding Zinc Ion Battery

Aqueous zinc battery promotes great interest due to its high safety and significant energy density. However, the Zn anode shows severity of dendrite growth and hydrogen evolution reaction (HER). Addressing these challenges requires effective manipulation of the inner Helmholtz plane (IHP). Thereby, we secure a novel strategy for generating water‐locking IHP through the in‐situ growth of a hygroscopic Zn‐ethanolamine (Zn‐EA) protective layer on the Zn surface. This layer forms via coordination between ZnCl 2 salt and ethanolamine, effectively reducing the intermediate/free water. Moreover, ethanolamine contains zincophilic sites (C–O and –NH 2 ) further promote the uniform Zn deposition. The in‐situ Raman confirms the ability of the hygroscopic layer to lock the active water away from the Zn surface. Therefore, Zn‐EA@Zn anode exhibits an impressive life stability of 288 h at 20 mA cm −2 and 20 mAh cm −2 with an extended lifespan of 2100 h at 1 mA cm −2 and 1 mAh cm −2 . Furthermore, the Zn‐EA@Zn||Cu demonstrates 100% Coulombic efficiency over 4275 cycles, while Zn‐EA@Zn ||V 2 O 3 /NC full cell retains a specific capacity of 170 mAh g −1 at 5 A g −1 after 1000 cycles, and the pouch cell maintains 0.5 mAh cm −2 after 460 cycles at 2 mA cm −2 . Therefore, this approach is paving the way for the development of advanced zinc metal batteries.