Mixed-dimensional V2CTx/Ti3C2Tx composite interlayer to boost electrochemical performance of Li-S batteries

Weiqi Zhang; Wenchao Zhang; Jing Yao; Huiqing Lu; Xitian Zhang; LiLi Wu

doi:10.3389/fchem.2022.1020538

Mixed-dimensional V₂CT_x/Ti₃C₂T_x composite interlayer to boost electrochemical performance of Li-S batteries

Front Chem. 2022 Sep 30:10:1020538. doi: 10.3389/fchem.2022.1020538. eCollection 2022.

Authors

Weiqi Zhang¹, Wenchao Zhang¹, Jing Yao¹, Huiqing Lu¹, Xitian Zhang¹, LiLi Wu¹

Affiliation

¹ Key Laboratory for Photonic and Electronic Bandgap Materials, Ministry of Education, School of Physics and Electronic Engineering, Harbin Normal University, Harbin, China.

Abstract

A mixed-dimensional V₂CT_x/Ti₃C₂T_x composite interlayer was successfully prepared to tackle severe polysulfide (LiPS) shuttling and sluggish sulfur redox kinetics for high-performance lithium-sulfur batteries. In the unique nanoarchitecture, two-dimensional Ti₃C₂T_x nanosheets served as a stable skeleton with superb electronic conductivity, good mechanical strength, and high polysulfide adsorption, whereas one-dimensional V₂CT_x nanorods played a crucial role in chemisorbing LiPSs and catalyzing the conversion of LiPSs due to their high polarity and electrocatalysis. With the synergistic effect of V₂CT_x and Ti₃C₂T_x composite nanostructures, the cells with the mixed-dimensional V₂CT_x/Ti₃C₂T_x composite interlayer showed an impressive long-term cycling stability and small capacity decay rate of 0.062% per cycle over 600 cycles at 1 C and exhibited an outstanding rate capability of 935.3 mAh·g^-1 at 2 C.

Keywords: V2CTx/Ti3C2Tx; lithium–sulfur batteries; polysulfides; separator; shuttling; sulfur redox kinetics.