Constructing oxygen deficiency‐rich V <sub>2</sub> O <sub>3</sub> @PEDOT cathode for high‐performance aqueous zinc‐ion batteries
Dongfei Sun, Zijuan Wang, Tian Tian, Xin‐Yao Yu, Dandan Yu, Xiaozhong Zhou, Guofu Ma, Ziqiang Lei
Abstract
Abstract Aqueous zinc‐ion batteries (AZIBs) have attracted widespread attention due to the advantages of high safety and environmental friendliness. Although V 2 O 3 is a promising cathode, the strong electrostatic interaction between Zn 2+ and V 2 O 3 crystal, and the sluggish reaction kinetics still limit their application in AZIBs. Herein, the oxygen defects rich V 2 O 3 with conducive poly (3,4‐ethylenedioxythiophene) (PEDOT) shell (V 2 O 3 ‐O d @PEDOT) was fabricated for AZIBs by combining the sulfur‐assisted thermal reduction and in‐situ polymerization method. The introduced oxygen vacancies of V 2 O 3 –O d @PEDOT weaken the electrostatic interaction between Zn 2+ and the host material, improving the interfacial electron transport, while the PEDOT coating enhances the structural stability and conductivity of V 2 O 3 , thus accelerating the reaction kinetics. Based on the advantages, V 2 O 3 –O d @PEDOT electrode delivers a reversible capacity of 495 mAh·g −1 at 0.1 A·g −1 , good rate capability (189 mAh·g −1 at 8.0 A·g −1 ), and an impressive cycling stability with 90.1% capacity retention over 1000 cycles at 8.0 A·g −1 . The strategy may provide a path for exploiting the other materials for high performance AZIBs.