Air-stabilized pore structure engineering of antimony-based anode by electrospinning for potassium ion batteries

Due to the large ionic radius and associated slow reaction kinetics of potassium ions, it is a major chal-lenge to find suitable anode materials for potassium-ion batteries. Herein, we design porous antimony -based nanofibres via a simple, low-cost and large scalable method to promote the electrochemical per-formance of potassium-ion batteries. Unlike those traditionally treated in inert atmospheres, using the different decomposition processes of polyacrylonitrile and polyvinylpyrrolidone in air, we obtain anti-mony trioxide embedded in porous carbon nanofibres (Sb2O3@PCN). The porous structure can promote the permeation of electrolyte into electrode materials and increase the active sites of the redox reaction. The porous carbonaceous fibre skeleton structure establishes a fast ion transport channel and enhances the kinetic performance. In a concentrated 5 M potassium bis(fluorosulfonyl)-imide/dimethyl carbonate electrolyte, Sb2O3@PCN exhibits a stable discharge specific capacity of 437.3 mAh g-1 at a current density of 100 mA g-1 after 50 cycles, which is much higher than that treated in a N2 atmosphere (247.5 mAh g-1). This method provides a new approach for the preparation of efficient potassium-ion battery electrode materials. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

Finding suitable anode materials for potassium-ion batteries is a major challenge due to the slow reaction kinetics of potassium ions. This study presents the design of porous antimony-based nanofibers to enhance the electrochemical performance of potassium-ion batteries. The porous structure promotes electrolyte permeation and increases active sites, while the carbonaceous fiber skeleton facilitates fast ion transport. The resultant Sb2O3@PCN exhibits a stable discharge specific capacity and outperforms the N2-treated counterpart. This method offers a new approach for efficient potassium-ion battery electrode materials.