Construction of Hierarchical Flower‐Shaped (NH4)2V3O8/rGO with Enhanced Zinc Storage Performance

• Published in: ChemElectroChem Vol. 8; no. 23; pp. 4618 - 4624
• Main Authors: Pan, Zikang, Ru, Qiang, Zheng, Minghui, Xu, Wengang, Wu, Jinlin, Zhang, Jun, Francis Chi‐Chun Ling, Li, Wie
• Format: Journal Article
• Language: English
• Published: Weinheim John Wiley & Sons, Inc 01.12.2021
• Subjects: Cathodes; Cycles; Electrode materials; Electrolytic cells; Graphene; Low conductivity; Stability; Vanadium; Xanthan; Zinc
• ISSN: 2196-0216
• DOI: 10.1002/celc.202101245

Vanadium‐based cathode materials are being widely investigated in aqueous zinc‐ion batteries (ZIBs) due to their high specific capacity. However, poor cycling stability and low conductivity limit their practical applications. Herein, the hierarchical flower‐shaped (NH4)2V3O8/reduced graphene oxide (denoted as NVO/rGO) composite is designed to harvest high‐efficiency Zn storage. Benefiting from the stable layered structure of NVO, the prominent pseudocapacitance, and excellent conductivity of rGO, the NVO/rGO composite exhibits a high specific capacity of 375.3 mAh g−1 at 0.2 A g−1, excellent cycling stability of 265.0 mAh g−1 after 3700 cycles at 5.0 A g−1 (capacity retention over 95.3 %), and outstanding rate performance of 263.9 mAh g−1 at 10.0 A g−1 by using traditional coin cells. To further verify the practicability of the NVO/rGO cathode, flexible electrode and xanthan gum electrolyte are adopted to assemble quasi‐solid‐state ZIBs, which exhibit a great specific capacity of 185.0 mAh g−1 at 0.5 A g−1 and good stability under different bending angles with an impressive capacity retention of 92.2 % after cycling. This study illustrates that hierarchical flower‐shaped NVO/rGO has a promising potential as aqueous or quasi‐solid‐state ZIBs cathode and improves the application of vanadium‐based materials.