Analysis of the characteristics and mass transfer mechanism of 3D-printed graphene aerogel composite electrode based on digital reconstruction technology

Abstract

3D-printed graphene aerogel has attracted great attention in many fields, including energy storage, environmental protection and intelligent sensing areas. However, the study on the mass transfer performance of 3D-printed graphene aerogel is limited. This paper investigates the characteristics and mass transfer mechanism of 3D-printed graphene aerogel composite electrodes in vanadium redox flow battery (VRFB) based on digital reconstruction technology. Herein, the model of 3D-printed graphene aerogel composite electrode with realistic porous structure was digital reconstructed based on microcomputed tomography (μCT). Owing to the advantages of digital reconstruction, the mass transfer mechanism of vanadium ion in porous electrode can be revealed. The results show that the characteristic structure with large pores enhances the mass transfer performance of the 3D-printed graphene aerogel composite electrode and exhibits relatively high porosity, ion permeability and diffusivity. In the printed filament, the graphene sheets are arranged at a certain angle, and the electrolyte transfers along the direction of the graphene sheets. Furthermore, the proposed method based on digital reconstruction shows promising prospects for the optimal design of aerogel electrode for energy storage devices.