Direct ink writing (DIW) of graphene aerogel composite electrode for vanadium redox flow battery

Abstract

This paper proposes the reduced graphene oxide (rGO)/Super-P aerogel composite electrode with controllable porous structure based on direct ink writing (DIW). To inspect its potential in vanadium redox flow battery (VRFB), scanning electron microscope (SEM), X-ray energy dispersive spectrum (EDS), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) test and charge-discharge test are conducted. The results reveal that the composite aerogel electrode originated from GO/Super-P mass ratio of 2:1 exhibits the best cell performance. Ascribing to the high conductivity, high specific area and reasonable hierarchical porous structure, the cell with optimized rGO/Super-P aerogel electrode shows superior discharge capacity of 848.4 mA h at the current density of 80 mA cm−2, which increases by 14.9% compared to that equipped with traditional graphite felt (GF). Ascribing to the advantages of controllable porous structure, energy-saving and facile synthesis process originated from DIW, the proposed aerogel electrode may provide an alternative to GF and exhibit promising potential in VRFB.