A feasible strategy to enhance mass transfer property of carbon nanofibers electrode in vanadium redox flow battery. (10th September 2021)

• Record Type: Journal Article
• Authors: Jing, Minghua; Qi, Xiaochen; An, Xinyu; Ma, Xiaoxue; Fang, Dawei; Fan, Xinzhuang; Liu, Jianguo; Yan, Chuanwei
• Is Part Of: Electrochimica acta. Volume 390(2021)
• Publication Date: 2021-09-10
• Subjects: Vanadium redox flow battery -- Carbon nanofibers -- Porous electrode -- Mass transfer -- Electrochemical activity; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2021.138879
• Languages: English
• ISSNs: 0013-4686

Abstract

Hightlights: A novel spherical-filament binary carbon nanofibers electrode is easily constructed. The aperture of the carbon nanofibers electrode is increased properly. The mass transfer property of the new-type electrode is improved effectively. The ECNFs-SCMS exhibits enhanced electrochemical activity. Efficiencies and power density of VRFBs are highly improved. Abstract: Carbon nanofibers (ECNFs) electrode possess good electrochemcial reactivity towards the V 3+ /V 2+ and VO2 + /VO 2+ redox couples in vanadium redox flow battery (VRFB), while its inferior mass transfer property limits the cell power density seriously due to the lower porosity and poorer permeability. In order to improve the mass transfer property, starch based carbon microsphere (SCMS) of a few micrometers is synthesized by a green hydrothermal method and introduced into the electrospun precursor solution. Subsequently, a novel spherical-filament binary carbon nanofibers electrode (ECNFs-SCMS) is constructed by the controllable electrospining technique along with the subsequent heat treatment processes. The novel binary carbon nanofibers exhibits more loose structure, improved hydrophilia, increased oxygen contents and more defects, which result in the simultaneous improvement of electrochemical reaction area, electrocatalytic activity and mass transfer kinetics. The single VRFB cell with ECNFs-SCMS as electrodes shows higher energy efficiency and maximun power density as compared to the one with pure ECNFs electrodes. The results in this work suggest that improving permeability is a feasible strategy to enhance the mass transfer property of carbon nanofibers electrode.