MIL‐47(V) Derived V2O5@Carbon Core‐Shell Microcuboids with Oxygen Vacancies as Advanced Conversion Cathodes for High‐Performance Zinc‐Ion Batteries. Issue 10 (19th May 2022)

• Record Type: Journal Article
• Authors: He, Tianqi; Li, Jinhang; Luo, Zhengzhi; Zhang, Yuqiang; Zhao, Yingying; Zhang, Xitian; Chen, Yujin
• Is Part Of: ChemElectroChem. Volume 9:Issue 10(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-19
• Subjects: V2O5 cathode -- oxygen vacancies -- carbon shell -- zinc-ion battery -- metal-organic frameworks; Electrochemistry -- Periodicals; 541.37
• DOI: 10.1002/celc.202200178
• Languages: English
• ISSNs: 2196-0216

Abstract

Abstract: Vanadium pentoxide (V2 O5 ) 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 V2 O5 . Herein, a controllable strategy is proposed to synthesize V2 O5 @carbon core‐shell microcuboids with oxygen vacancies (V2 O5‐ x @CCSMs) derived from MIL‐47(V) used for cathodes of ZIBs. The obtained V2 O5‐ 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 V2 O5, oxygen vacancies and carbon shell. Further, ex‐situ XRD indicates V2 O5 undergoes a shrinking core model conversion reaction at initial cycling to a new phase of Zn3 V2 O7 (OH)2 ⋅ 2H2 O, which is an ideal host for Zn 2+ . Our work offers an innovative strategy to develop high‐capacity cathode in ZIBs. Abstract : V2 O5 @carbon core‐shell microcuboids with oxygen vacancies (V2 O5‐ x @CCSMs) derived from MIL‐47(V) were fabricated. The V2 O5‐ x @CCSMs//Zn system shows a high energy density of 130.9 Wh kg −1 at a high power density of 6545.5 W kg −1 .