Enhancing ion shuttling through hydrogen bonding effect in ZnV2O4 aqueous zinc ion battery cathode
Lei Tan, Zhao Li, Lei Wang, Yu Shang, Zhiguo Wang, Zhengwang Tong, Yan Li, Xiangming Li
Abstract
Layered vanadium oxide materials exhibit significant multielectron redox reactions and regulatable transfer channels for Zn 2+ insertion/extraction in rechargeable aqueous zinc-ion batteries (AZIBs). However, vanadium dissolution poses a severe challenge to achieving stable performance in AZIBs . In this work, we report an in-situ polymerization of polyaniline (PANI) on ZnV 2 O 4 (ZVO) materials, resulting in a cross-interlocked nanosheet morphology to inhibit vanadium dissolution. The high conductivity and unique π-conjugated structure of PANI effectively weaken the electrostatic interactions between Zn 2+ and the V-O layers, thereby enhancing the diffusion of Zn 2+ at the electrode material interface, suppressing the vanadium dissolution of ZnV 2 O 4 and stabilizing its structure framework. Concurrently, density functional theory (DFT) calculations further confirm that PANI can significantly modulate the electronic properties of the ZVO matrix. PANI forms robust hydrogen bonds with ZVO, resulting in an abundance of free Zn ions within the system, which accelerates electron/ion transfer kinetics, thereby enhancing the efficient storage performance of Zn 2+ and increasing specific capacity. The ZVO@PANI composite electrode exhibits high specific capacity (706.4 mAh g −1 at 0.1 A g −1 ), remarkable rate capability (350.2 mAh g −1 at 5 A g −1 ), and robust cycling performance. This study provides a reasonable strategy for designing high-performance cathode materials for aqueous zinc-ion batteries.