Holey aligned electrodes through in-situ ZIF-8-assisted-etching for high-performance aqueous redox flow batteries

• 作者: Jing Sun Haoran Jiang Chen Zhao Xinzhuang Fan Christopher Chao Tianshou Zhao
• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2021,（9）
• 所属期刊栏目: ARTICLES
• 页码范围: 904-913
• 页数: 10页
• 语种: 英文

摘要

Fabricating electrodes with large specific surface area (SSA) and high permeability has been the longstanding target in redox flow batteries (RFBs).In this work,we propose a novel ZlF-8-assisted etching approach to form holey fibers in the electrospinning process of aligned electrode structures.The etching approach allows the formation of holey fibers with small pores of ～50 nm,offering large active surface areas for redox reactions,while the aligned macrostructure with the holey fibers of 3-5 μm in diameter ensures a high permeability along the fiber direction.The application of the prepared electrodes to a vanadium redox flow battery (VRFB) enables an energy efficiency (EE) of 87,2％ at the current density of 200 mAcm-2,which is 13.3％ higher than that with conventional electrospun carbon electrodes.Even at high current densities of 300 and 400 mA cm-2,the battery still maintains energy efficiencies of 83.3％ and 79.3％.More excitingly,the prepared electrode yields a high limiting current density of 4500 mA cm-2 and a peak power density of 1.6 W cm-2.It is anticipated that the present electrospinning method combining the ZlF-8-assisted etching approach with a way to form ordered fiber structures will allow even more high-performance electrodes for RFBs in the future.