"Triple-synergistic effect" of K and PANI co-intercalation enabling the high-rate capability and stability of VO for aqueous zinc-ion batteries.

Vanadium-based materials are widely recognized as the primary candidate cathode materials for aqueous Zn-ion batteries (AZIBs). However, slow kinetics and poor stability pose significant challenges for widespread application. Herein, to address these issues, alkali metal ions and polyaniline (PANI) are introduced into layered hydrated VO (VO). Density functional theory calculations reveal that the synthesized (CHNH)KVO·0.92HO (KPVO), with K and PANI co-intercalation, exhibits a robust interlayer structure and a continuous three-dimensional (3D) electron transfer network. These properties facilitate the reversible diffusion of Zn with a low migration potential barrier and rapid response kinetics. The KPVO cathode exhibits a discharge specific capacity of 418.3 mAh/g at 100 mA/g and excellent cycling stability with 89.5 % retention after 3000 cycles at 5 A/g. This work provides a general strategy for integrating cathode materials to achieve high specific capacity and excellent kinetic performance.