Mn²⁺ Intercalation into Hydrated Vanadium Pentoxide Nanosheets for Highly Durable Zinc Ion Batteries

Aqueous Zn ion batteries are emerging energy storage devices with inexpensive, environmentally benign, and extremely safe characteristics. However, the increase of side reaction limits their further applications due to the lack of suitable cathode materials and water solvent as electrolytes. Herein, we report a kind of electrode material by inserting Mn 2+ into the interlayers of nanosheets. The introduction of Mn ion protects the integral structure during the fully charging–discharging process. In addition, the presence of crystallized water also plays an electrostatic shielding role, which favors the embedding and de-embedding of zinc ions. The Zn/MVO devices deliver a reversible specific capacity of 394.54 mAh/g at 0.2 A/g and long-term cycle stability.