Chemically assembling chromium vanadate into an urchin-like porous rich matrix with ultrathin nanosheets for rapid Zn2+ storage

Aqueous zinc ion battery (AZIB) is a promising battery system developed in recent years, which has the advantages of safety, environmental protection and low price. However, it is still a puzzle to develop and improve cathode materials with satisfactory performance. In this paper, the chromium vanadate (CrVO3) electrode material was reported for the first time. The obtained CrVO3 have mesoporous structure (the mesopore sizes: 2-50 nm), excellent conductivity, high surface area (129.3m(2) g(-1)) and uniform thickness of 2 nm, which provides a short path for rapid transfer of zinc ions, a large surface area for high pseudocapacitance, and sufficient voids to mitigate volume expansion. Given these structural advantages, the CrVO3 cathode delivers high capacities of 188.8 and 112.8 mAh g(-1) at 0.5 and 4 A g(-1) and excellent long cycle stability, respectively. More importantly, the Zn//CrVO3 battery provided an energy density of 231.9 Wh kg(-1) at a power density of 100.4 W kg(-1). Meanwhile, insight into the formation mechanism and Zn2+ storage mechanism by ex situ methods. The results show that the porous CrVO3 is a promising cathode material for AZIBs, which provide a valuable idea for the design of porous vanadate with significantly enhanced performances in electrochemical energy storage. (C) 2021 Elsevier Inc. All rights reserved.

Automated summary

This paper introduces a new electrode material, chromium vanadate (CrVO3), with excellent structural advantages and performance, providing a promising design idea for the cathode material of aqueous zinc ion batteries.