Oxygen Vacancy‐Rich NaV ₆ O ₁₅ Nanorods for Boosting Zn‐Ion Battery Performance

ABSTRACT Aqueous Zn‐ion batteries attract much attention due to their advantages of considerable theoretical energy capacity, high safety, environment friendly, and low cost. However, viable vanadium‐based cathode materials usually suffer from sluggish kinetics and limited stability. Herein, it is reported that NaV 6 O 15 nanorods (NaVO) with a diameter of 170 nm are successfully fabricated via a facile process of hydrothermal and subsequent annealing. After a process of reduction, the reduced NaV 6 O 15 nanorods (R‐NaVO) were obtained, with more oxygen vacancies and a higher tetravalent vanadium ratio than NaVO. As a result, R‐NaVO nanorods show much higher charge‐transfer rate and ion‐diffusion rate. Just due to the unique structure features, the assembled R‐NaVO//Zn battery can supply a higher capacity of 182.8 mAh g −1 at the current density of 1 A g −1 than 119.6 mAh g −1 of NaVO//Zn battery, and perform excellent cycling stability of 97.5% retention after 1000 charge/discharge cycles. This work provides a facile fabrication method for supplying high‐capacity and long‐life NaV 6 O 15 cathode materials and great practical value for the development of vanadium‐based aqueous Zn‐ion batteries in the future.