Stable zinc anode achieved through ultramicro long chain cationic surfactant as interface regulator in aqueous electrolyte

The large-scale commercialization of aqueous zinc ion batteries (AZIBs) is still restricted due to rampant side reactions and serious dendritic growth. Therefore, a high-efficiency, low-cost and environment-friendly multifunctional electrolyte additive hexadecyltrimethylammonium bisulfate (CHN(HSO4)) is developed and first introduced into 2 M ZnSO4 solution as a cationic surfactant to enhance the stability of Zn-ion batteries (ZIBs). Electrochemical experiments and theoretical calculations confirm that long-chain CHN+ cation can regulate the Zn2+ ions nucleation to inhibit dendrite growth and isolate H2O molecules to inhibit harmful side reactions with the preferential adsorption on the Zn metal surface. Because of the effective protection of CHN+ cation adsorption layer, the corrosion of the Zn anode surface is inhibited, and the maximum corrosion inhibition efficiency exceeds 90%. Furthermore, with an ultra-micro dosage of 0.01 mM CHN(HSO4) electrolyte, the stable plating/stripping for the symmetric Zn|Zn cell without dendritic growth is realized for 3000 h at 1 mA cm−2 for 0.5 mAh cm−2, which is almost 21 times of that without additives. Meanwhile, high coulombic efficiency (CE) of 99.6% for Zn plating-stripping is achieved, and the Zn|MnO2 full cell exhibits stable cycling performance and high specific capacity, showing great potential for practical application.