Anionic Surfactant-Mediated Hydrogen-Bond Regulation Enables Highly Reversible Zn Anode via Guided Zn²⁺ Deposition

The pursuit of high specific energy and long lifespan aqueous zinc ion batteries (AZIBs) remains a long-standing task. However, the reversibility of the Zn anode, especially under high utilization conditions, is severely hampered by the hydrogen evolution reaction (HER) and dendrite growth, which hinder the practical application of AZIBs. In this study, Magnesium Ascorbyl Phosphate (MAP), an anionic surfactant, was selected as an electrolyte additive to modulate the electrolyte hydrogen-bond network and regulate Zn²⁺ deposition. As a result, the strong hydrogen-bond proportion increased from 36.9% to 40.17%, which mitigated HER and prolonged the anode lifespan. Moreover, an instantaneous Zn²⁺ deposition mode with a Pearson coefficient of 0.97 was recorded, which effectively prevented dendrite growth and improved the anode utilization. The Zn||Zn symmetric cells with MAP additives exhibit an extremely prolonged lifespan of 3102 h, which is 25-fold higher than the bare Zn electrode at a Zn depth of discharge (DOD) of 13%. More importantly, the full battery exhibits an overwhelming result of capacity retention of 89.84% even after 8000-time cycling with I₂@KB cathode (10.2 mg cm^-2, DOD = 6.1%) at 1 A g^-1. This work provides a profound insight into regulating deposition behavior through electrolyte hydrogen-bond engineering.