Imidazole-2-carboxaldehyde additive participation in construction of artificial SEI enabling ultra-stable Zn anode

Poor stability caused by side reactions such as corrosion, Zn dendrite and hydrogen evolution are crucial factors hindering commercial application in queous zinc ion energy storage systems. This article offers a strategy, zinc-rich artificial solid electrolyte interphase (ASEI) layer with polar groups by imidazole-2-carboxaldehyde (2-ICA) electrolyte additive, which helps form stable electrode/electrolyte interface and rapid Zn 2+ transfer interface with low resistance. Firstly, the chelation with Zn 2+ of 2-ICA and its zincophilic capability enable the rapid formation of the ASEI layer and result in more sites for initial nucleation, which then guides the uniform Zn 2+ deposition. Additionally, the introduced ASEI with polar groups accelerates the de-solvation kinetics of Zn 2+ and the Zn 2+ transfer ability in electrode/electrolyte interface, which enable high-rate charge and discharge. Therefore, the symmetric battery based on 2-ICA electrolyte exhibits excellent cycling stability at 20 mA cm −2 (cycling up to 800 h). At the same time, assembled Zn//Cu also has a high average Coulombic efficiency (99.2 %). The zinc-ion hybrid capacitors (ZICs) assembled based on this electrolyte also exhibit outstanding electrochemical properties. This work offers a simple and novel way to realize high performance and great safety zinc-based energy storage devices.