In-situ preparation of amorphous VO2@rGO cathode for ultra-high capacity and ultra-long cycle life aqueous zinc ion batteries

Jian Wu; Zhanhong Yang; Hongzhe Chen

doi:10.1016/j.jcis.2023.06.124

In-situ preparation of amorphous VO₂@rGO cathode for ultra-high capacity and ultra-long cycle life aqueous zinc ion batteries

J Colloid Interface Sci. 2023 Nov:649:372-383. doi: 10.1016/j.jcis.2023.06.124. Epub 2023 Jun 19.

Authors

Jian Wu¹, Zhanhong Yang², Hongzhe Chen¹

Affiliations

¹ Hunan Province Key Laboratory of Chemical Power Source, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China; Innovation Base of Energy and Chemical Materials for Graduate Students Training, Central South University, Changsha 410083, China.
² Hunan Province Key Laboratory of Chemical Power Source, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China; Innovation Base of Energy and Chemical Materials for Graduate Students Training, Central South University, Changsha 410083, China. Electronic address: zhyangcsu611@163.com.

PMID: 37354794
DOI: 10.1016/j.jcis.2023.06.124

Abstract

Aqueous zinc-ion batteries (AZIBs) are considered as a promising alternative to lithium-ion batteries for stationary energy storage due to their environmental benignity and cost-effectiveness. However, the development of AZIBs continues to be plagued by a lack of cathode materials with high specific capacity and superior lifetime. Herein, we in-situ synthesize amorphous VO₂@rGO assisted by controlling the charging cut-off voltage. Experimental results and theoretical calculations confirm that the amorphous VO₂(A)@rGO can effectively reduce the migration energy barrier of Zn²⁺, improve the conductivity of the electrode, and promote the insertion/extraction of Zn²⁺. Consequently, the Zn//VO₂(A)@rGO battery exhibits an ultra-high specific capacity of 527.0 mAh·g^-1 at 1 A·g^-1 after 100 cycles, an ultra-long cycle stability of 183.4 mAh·g^-1 at 20 A·g^-1 after 30,000 cycles, and an energy of 316.1 Wh·Kg^-1 at a power density of 6082.9 W·Kg^-1 power density. Meanwhile, we reveal that the amorphous VO₂@rGO electrode follows a hybrid mechanism of classical Zn²⁺ insertion/de-insertion and the reversible phase transition from amorphous VO₂ to V₂O₃. This study highlights that in-situ preparation of amorphous VO₂@rGO cathode materials by controlling the charging voltage interval, opening up further possibilities for the development of high-performance AZIB cathodes.

Keywords: Amorphous VO(2)@rGO; Aqueous zinc-ion batteries; High capacity; Ultra-long cycling life; Voltage-window regulated; Zinc storage mechanism.