Reversibly Compressible, Highly Elastic, and Durable Graphene Aerogels for Energy Storage Devices under Limiting Conditions

Abstract

High porosity combined with mechanical durability in conductive materials is in high demand for special applications in energy storage under limiting conditions, and it is fundamentally important for establishing a relationship between the structure/chemistry of these materials and their properties. Herein, polymer-assisted self-assembly and cross-linking are combined for reduced graphene oxide (rGO)-based aerogels with reversible compressibility, high elasticity, and extreme durability. The strong interplay of crosslinked rGO (x-rGO) aerogels results in high porosity and low density due to the re-stacking inhibition and steric hinderance of the polymer chains, yet it makes mechanical durability and structural bicontinuity possible even under compressive strains because of the coupling of directional x-rGO networks with polymer viscoelasticity. The x-rGO aerogels retain >140% and >1400% increases in the gravimetric and volumetric capacitances, respectively, at 90% compressive strain, showing reversible change and stability of the volumetric capacitance under both static and dynamic compressions; this makes them applicable to energy storage devices whose volume and mass must be limited.

Carbon Nanotubes and Graphene for Flexible Electrochemical Energy Storage: from Materials to Devices

“…No significant change was observed for compressed SCs at 50% applied strain. Hong et al [ 215 ] developed SCs with reversible compressibility and mechanical durability by a PVA-assisted self-assembly and cross-linking of rGO. With the aid of PVA, the rGO aerogel was covalently cross-linked.…”

A Switchable and Compressible Carbon Nanotube Sponge Electrocapillary Imbiber

“…[ 8,31 ] Our fi ndings here support the argument that one can use electrocapillarity to control the electrolyte wettability on CNTs so as to control the imbibition dynamics into CNT sponges. The electrocapillary behavior of CNT sponges may also exist in other carbon aerogels such as the graphene aerogels reported recently, [32][33][34] based on which high-performance imbibition systems may be developed.…”

Recent Progress in Multifunctional Graphene Aerogels

“…Polymer-Assisted Self-Assembly Hong et al (2015) established polymer-assisted self-assembly with a cross-linking approach for the development of reversibly compressible, highly elastic, durable GAs. Cross-linked rGO (x-rGO) was the factor responsible for providing high porosity along with large surface area owing to the re-stacking inhibition and steric hindrance of the polymer chains.…”

“…It showed specific capacitance of 311 F g −1 at current density of 1 A g −1 and showed high specific capacitance (262 Fg ) even at 20 A g −1 current density. Hong et al (2015) developed a double cross-linking strategy for the formation of reversibly compressible, highly elastic, durable GAs using PVA and glutaraldehyde for energy storage devices under limiting conditions. The crosslinked rGO aerogels retain >140% and >1400% enhancements in the gravimetric and volumetric capacitances, respectively, at 90% compressive strain while both volumetric and gravimetric capacitances of rGO were not measured at the breaking point (~60% compressive strain).…”