A dual-functional electrolyte additive displaying hydrogen bond fusion enables highly reversible aqueous zinc ion batteries

In recent years, aqueous zinc-ion batteries (AZIBs) have attracted significant attention in energy storage due to their notable advantages, including high safety, low cost, high capacity, and environmental friendliness. However, side reactions like hydrogen evolution and zinc (Zn) dendrites can significantly impact their Coulombic efficiency (CE) and lifespan. Effectively addressing these issues has become a focus of research in this field. In our study, dimethyl sulfoxide (DMSO) and nanodiamonds (NDs) were used to optimize the electrolyte of AZIBs. Benefiting from the hydrogen bond fusion of DMSO and NDs, which regulates the Zn deposition behavior, effectively inhibiting the growth of Zn dendrites, hydrogen evolution, and corrosion. The Zn | |Zn symmetric cells using NDs-DMSO-ZS demonstrate exceptional cycling stability for over 1500 h at 1 mA cm−2, while the Zn//Cu asymmetric cells achieve up to 99.8% CE at 2 mA cm−2. This study not only shows the application prospects of electrolyte optimization in enhancing AZIBs performance, but also provides a reference for the advancement of electrolyte technology in advanced AZIBs technology. Aqueous zinc ion batteries represent promising next-generation energy storage systems, but unwanted side reactions such as hydrogen evolution and zinc dendrite formation can significantly impact their Coulombic efficiency and lifespan. Here, dimethyl sulfoxide and nanodiamond additives are introduced to a ZnSO4 electrolyte, effectively inhibiting side reactions and dendrite formation through hydrogen bond fusion, and enabling exceptional cycling stability for over 1500 h at 1 mA cm−2.