A widely used nonionic surfactant with desired functional groups as aqueous electrolyte additives for stabilizing Zn anode

Abstract Aqueous Zn‐ion batteries (AZIBs) have emerged as potential candidates for Li‐ion batteries due to their intrinsic safety and high capacity. However, metallic Zn anodes encounter dendrite growth and water‐induced corrosion, rendering poor stability and severe irreversibility at the electrode/electrolyte interface during cycling. To stabilize the Zn anode, we report a low‐cost and effective nonionic surfactant, Tween‐20 polymer, as an electrolyte additive for AZIBs. For Tween‐20, sequential oxyethylene groups tended to be preferentially adsorbed on the Zn electrode to form a shielding layer for regulating uniform Zn nucleation. Moreover, the hydrophobic hendecyl chains prevented H 2 O‐induced corrosion on the Zn anode surface. Benefiting from the desired functional groups, when only trace amounts of Tween‐20 (0.050 g·L −1 ) were used, the Zn anode displayed good cycling stability over 2170 h at 10 mA·cm −2 and a high average Coulombic efficiency of 98.94% over 1000 cycles. The Tween‐20 polymer can also be effectively employed in MnO 2 /Zn full batteries. Considering their toxicity, price and amount of usage, these surfactant additives provide a promising strategy for realizing the stability and reversibility of high‐performance Zn anodes.