PEDOT-intercalated NH4V3O8 nanobelts as high-performance cathode materials for potassium ion batteries

Changdong Chen; Qiang Deng; Qimeng Zhang; Pengyuan Dong; Wentao Zhong; Junhua Hu; Xiongwu Kang; Chenghao Yang

doi:10.1016/j.jcis.2022.11.101

PEDOT-intercalated NH₄V₃O₈ nanobelts as high-performance cathode materials for potassium ion batteries

J Colloid Interface Sci. 2023 Mar:633:619-627. doi: 10.1016/j.jcis.2022.11.101. Epub 2022 Nov 24.

Authors

Changdong Chen¹, Qiang Deng², Qimeng Zhang², Pengyuan Dong², Wentao Zhong², Junhua Hu³, Xiongwu Kang², Chenghao Yang⁴

Affiliations

¹ Guangzhou Key Laboratory for Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; College of Chemistry and Environmental Engineering, Pingdingshan University, Pingdingshan 467000, China.
² Guangzhou Key Laboratory for Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
³ School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, China.
⁴ Guangzhou Key Laboratory for Surface Chemistry of Energy Materials, New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China. Electronic address: esyangc@scut.edu.cn.

PMID: 36470141
DOI: 10.1016/j.jcis.2022.11.101

Abstract

Potassium ion batteries (PIBs) have great potential to replace lithium ion batteries (LIBs) for large-scale energy storage applications because of the low cost and earth abundance of potassium resources. However, it is critically challenging to exploit an appropriate cathode material to accommodate the large size of K⁺. Herein, a conducting polymer (PEDOT) intercalation method is utilized to tailor the interlayer spacing of NH₄V₃O₈ nanobelts from 7.8 Å to 10.8 Å, and afford rich oxygen vacancies inside the vanadate, thus enhancing its electronic conductivity and accelerating the K⁺ insertion/extraction kinetics. Benefiting from these features, PEDOT-intercalated NH₄V₃O₈ (PNVO) nanobelts deliver an improved capacity of 87 mA h g^-1 at 20 mA g^-1, high rate capability of 51 mA h g^-1 at 500 mA g^-1, and a stable cycle life (capacity retention of 92.5 % after 100 cycles at 50 mA g^-1). Even cycled at 200 mA g^-1, PNVO nanobelts feature a long cycle life over 300 cycles with a capacity retention of 71.7 %. This work is of great significance for exploitation of PIBs cathode with improved electrochemical performance through pre-intercalation and defect engineering.

Keywords: Cathode materials; NH(4)V(3)O(8) nanobelts; Oxygen vacancies; PEDOT intercalation; Potassium ion batteries.