Аңдатпа
Considerable potential for large-scale energy storage applications is exhibited by aqueous zinc-ion batteries. However, their development is severely hindered by interfacial issues at the anode, such as dendrite growth, hydrogen evolution reaction, and corrosion. Polymeric functional additives have been widely employed to address these challenges. Nevertheless, their effectiveness is often constrained by insufficient hydration in aqueous electrolytes. This hydration deficiency primarily stems from the weak polarity of many polymers, which impedes zinc-ion transport and consequently compromises battery performance. To overcome the issue of inadequate hydration and restricted ion transport associated with conventional polymer additives, a strategy involving the design of a superhydrophilic polar polymer-based functional additive was proposed to construct a functional interphase layer on the zinc anode. In line with this strategy, an ultra-hydrophilic polymer-based additive capable of serving as a zinc-ion transport channel has been designed. Density functional theory (DFT) calculations reveal that PAAS exhibits strong zincophilicity, with a calculated adsorption energy of −5.07 eV for the polyacrylate anion on the Zn surface, which is significantly stronger than that of H 2 O molecules (−0.24 eV). This substantial energy difference thermodynamically drives the preferential and robust adsorption of PAAS onto the zinc anode, in situ forming a dense, zincophilic, and polyacrylate-rich interphase. This interphase plays multiple roles: with a synergistic mechanism: the preferential adsorption of PAA − onto the Zn surface forms a protective layer that dominates the suppression of initial side reactions and guides uniform nucleation, while its participation in the primary solvation sheath concurrently modulates the Zn 2+ solvation structure to facilitate homogeneous ion transport. Consequently, the Zn||Zn symmetric cell with the optimal PAAS-modified electrolyte achieves an ultra-long cycling life of 4380 h at a current density of 0.5 mA cm −1 . This work provides a simple and practical electrolyte design strategy based on interfacial energy regulation for constructing high-performance and durable aqueous zinc-ion batteries. • To address the issues of insufficient hydration and restricted ion transport in polymer additives for aqueous zinc-ion batteries, sodium polyacrylate was designed as a hydrophilic polymer additive. • Density functional theory calculations confirmed its strong zinc-philic nature (adsorption energy on zinc surface: −5.07 eV), enabling spontaneous adsorption and the formation of a stable polyacrylate-rich interfacial layer. • The PAAS-modified electrolyte enabled an ultralong cycling life of 4380 h at 0.5 mA cm −2 in Zn||Zn cells and achieved a high Coulombic efficiency of 99.50% over 457 cycles in Zn||Cu cells.