The effect of nanoscale architecture on ionic diffusion in rGo/aramid nanofiber structural electrodes

Abstract

Structural energy storage is a rapidly emerging area with tantalizing applications such as integrated devices in textiles, smart suits, and uniforms. Due to several outstanding properties, graphene oxide (rGO)/aramid nanofiber (ANF) composite material has emerged as a compelling choice as a structural electrode for supercapacitors and batteries. A key question of significant technological relevance pertains to what kind of nanoscale architecture motifs may lead to enhanced ionic diffusivity - the key characteristic dictating the overall performance of the electrode. In this study, we attempt to address precisely this question, through multiphysics simulations, in the context of several "experimentally realizable, layered" architectures. We investigate different arrangements (staggered and aligned) and various degrees of waviness of the rGO nanosheets inside the ANF polymer matrix. Our results indicate that decreasing waviness of the rGO sheets can enhance the ion diffusivity in the staggered and aligned arrangements of the electrode material, while this effect is stronger in the staggered arrangements than in the aligned arrangements. The insights obtained from this study can lead to a more effective design of electrode architectures.