Vanadium dioxide (VO2) is a polymorphic material of interest for aqueous zinc-ion batteries (AZIBs). As one of its most attractive phases, metastable VO2(B) offers a high theoretical capacity. Unfortunately, its practical use is hindered by sluggish reaction kinetics and severe dissolution issues, rendering it unstable in aqueous electrolytes. To address these challenges, we herein report a dual-function strategy designed to simultaneously enhance the kinetics and suppress dissolution. Through the intercalation of dual metal ions (Y3+ and Al3+) and highly conductive poly(3,4-ethylenedioxythiophene) (PEDOT) encapsulation, the as-prepared YAlVO2@PEDOT exhibited a high specific capacity of 335.61 mAh g–1 at 1 A g–1. At 5 A g–1, it demonstrated a high specific capacity of 275.59 mAh g–1 with a capacity retention of 80.3% after 1000 cycles. Ex situ characterizations further verified that, benefiting from the protective hydrophobic PEDOT layer and expanded interlayer spacing, the reaction kinetics was also improved. This strategy provided a promising approach for developing VO2 materials to achieve high-performance AZIBs.
Zhang et al. (Wed,) studied this question.