MIL‐47(V) Derived V2O5@Carbon Core‐Shell Microcuboids with Oxygen Vacancies as Advanced Conversion Cathodes for High‐Performance Zinc‐Ion Batteries

Abstract Vanadium pentoxide (V 2 O 5 ) has been considered one of the most promising cathodes for zinc‐ion batteries (ZIBs) due to its outstanding theoretical capacity (589 mAh g −1 ). However, it remains great challenge to achieve the high capacity, limited to the poor electronic conductivity and sluggish ionic diffusion kinetics of V 2 O 5 . Herein, a controllable strategy is proposed to synthesize V 2 O 5 @carbon core‐shell microcuboids with oxygen vacancies (V 2 O 5‐ x @CCSMs) derived from MIL‐47(V) used for cathodes of ZIBs. The obtained V 2 O 5‐ x @CCSMs cathode delivers high capacities of 485.4 and 392.1 mAh g −1 at 0.1 and 2.0 A g −1 , respectively. The superior electrochemical performances originate from the nano‐sized particles of V 2 O 5 , oxygen vacancies and carbon shell. Further, ex‐situ XRD indicates V 2 O 5 undergoes a shrinking core model conversion reaction at initial cycling to a new phase of Zn 3 V 2 O 7 (OH) 2 ⋅ 2H 2 O, which is an ideal host for Zn 2+ . Our work offers an innovative strategy to develop high‐capacity cathode in ZIBs.