Zincophilic and Hydrophobic Groups of Surfactant-Type Electrolyte Additive Enabled Stable Anode/Electrolyte Interface Toward Long-Lifespan Aqueous Zinc Ion Batteries

Rechargeable aqueous zinc-ion batteries, while promising in terms of safety, cost-effectiveness, and eco-friendliness, face challenges such as zinc dendrite growth and parasitic reactions at the anode/electrolyte interface. Herein, a low-cost cationic surfactant, dodecyltrimethyl ammonium chloride (DTAC) is deployed as a competitive additive in traditional ZnSO4 electrolyte to stabilize the zinc anode. Firstly, the DTAC additive disrupts the hydrogen bonding network and regulates the solvation structure. Secondly, the DTA+ cations preferentially adsorb onto the anode surface vertically, forming a dodecyl chain hydrophobic layer that suppresses the side reactions. Thirdly, the hydrophobic layer not only elevates the nucleation overpotential of Zn2+ ions but also limits their 2D diffusion at the anode surface, triggering oriented deposition of metal zinc and inhibiting dendrite growth. Leveraging these triple-regulation effects, the Zn//Zn symmetric cell with DTAC additives achieves an ultra-long cycle life of 2000 hours at a current density of 1 mA cm−2 with 1 mAh cm−2. Furthermore, the Zn//MnO2 full cell with DTAC additive demonstrates promising performance, delivering an initial capacity of 149.44 mAh g−1 at 5 A g−1 and retaining 83.02% of its capacity after 2000 cycles. These results underscore the potential of DTAC additives in advancing the industrialization of AZIBs.