Construction of a Hydrophobic TiO₂ Interfacial Layer on Zinc Anodes and Study of Its Cycling Performance

To address the persistent challenges of dendrite growth, hydrogen evolution, and corrosion in aqueous Zn-ion batteries, this study demonstrates the construction of a zincophilic-hydrophobic TiO₂ interfacial layer on the Zn anode. This was achieved by grafting hydrophobic methacryloxypropyl groups (CH₂ ＝ C(CH₃)COO(CH₂)₃—) onto nano-TiO₂ via the silane coupling agent (KH570). The grafted hydrocarbon chains act as a hydrophobic barrier, impeding H₂O diffusion and promoting the desolvation of hydrated Zn²⁺ to suppress side reactions. Simultaneously, the abundant Ti—OH groups on TiO₂ serve as zincophilic sites, increasing local Zn²⁺ concentration and facilitating uniform deposition. The modified Zn anode exhibited a transition from hydrophilic (79°) to hydrophobic (105°) wetting behavior and a significantly reduced charge-transfer resistance. Consequently, it delivered exceptional cycling stability exceeding 800 hours at 1 mA·cm^-2 and 1 mAh·cm^-2. This work provides a novel interfacial design strategy for high-performance zinc anodes.