Exploration of bifunctional Vanadium-based Metal-Organic framework with double active centers for Potassium-ion batteries

Qijiu Deng; Runrun Wang; Yumeng Wang; Zhaohui Yang; Bo Gou; Jilin Li; Yinglin Yan; Rong Yang

doi:10.1016/j.jcis.2022.08.098

Exploration of bifunctional Vanadium-based Metal-Organic framework with double active centers for Potassium-ion batteries

J Colloid Interface Sci. 2022 Dec 15;628(Pt B):556-565. doi: 10.1016/j.jcis.2022.08.098. Epub 2022 Aug 17.

Authors

Qijiu Deng¹, Runrun Wang², Yumeng Wang², Zhaohui Yang³, Bo Gou³, Jilin Li⁴, Yinglin Yan², Rong Yang⁵

Affiliations

¹ School of Material Science and Engineering, Xi'an University of Technology, Xi'an 710048, China; State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Hainan 570228, China. Electronic address: dengqijiu@xaut.edu.cn.
² Institute of Chemical Power Sources, School of Science, Xi'an University of Technology, Xi'an 710048, China.
³ School of Material Science and Engineering, Xi'an University of Technology, Xi'an 710048, China.
⁴ School of Material Science and Engineering, Xi'an University of Technology, Xi'an 710048, China; Institute of New Materials, Guangdong Academy of Sciences, Guangzhou, China.
⁵ School of Material Science and Engineering, Xi'an University of Technology, Xi'an 710048, China. Electronic address: yangrong@xaut.edu.cn.

PMID: 36007420
DOI: 10.1016/j.jcis.2022.08.098

Abstract

Exploration of suitable electrode hosts with large open channels that can reversibly accommodate K⁺ with large radius have been extensively investigated. Nevertheless, the reported inorganic counterparts were inevitably restricted by the difficulty of large K⁺ diffusion capability in crystal structure and the huge volume change. Herein, we report a bifunctional vanadium-based metal-organic framework (MIL-47) with double active centers and larger lamellar spacing that could serve as both cathode and anode material, respectively by controlling the redox potential range in potassium-ion batteries. The results suggest that the stable K-storage mechanism is the reversible rearrangement of the conjugated carboxyl groups of organic terephthalic acid into enolate and the reversible redox activity of V ions, with the specific capacity of 272 mAh g^-1 (0.01-1.5 V) and 50 mAh g^-1 (1.5-3.8 V) at the current density of 10 mA g^-1 for MIL-47 anode and MIL-47 cathode, respectively. The unsaturated functional group of MIL-47 and the intermediate bridged V atom not only provide multi-dimensional channels for electron and ion transport but also stabilize its crystal structure. Additionally, a symmetric full-cell in potassium-ion batteries based on MIL-47 was constructed successfully by avoiding the utilization of K metal with safety concerns. Our results provide new insight into structure design for next-generation large-scale energy storage applications.

Keywords: Bifunctional materials; Electrochemical performance; Potassium-ion batteries; Reaction mechanism.