Boosting the Performance of Graphene Cathodes in Na-O2 Batteries by Exploiting the Multifunctional Character of Small Biomolecules

The role of graphene aerogels in rechargeable batteries

Energy storage systems, particularly rechargeable batteries, play a crucial role in establishing a sustainable energy infrastructure. Today, researchers focus on improving battery energy density, cycling stability, and rate performance. This involves enhancing existing materials or creating new ones with advanced properties for cathodes and anodes to achieve peak battery performance. Graphene aerogels (GAs) possess extraordinary attributes, including a hierarchical porous and lightweight structure, high electrical conductivity, and robust mechanical stability. These qualities facilitate the uniform distribution of active sites within electrodes, mitigate volume changes during repeated cycling, and enhance overall conductivity. When integrated into batteries, GAs expedite electron/ion transport, offer exceptional structural stability, and deliver outstanding cycling performance. This review offers a comprehensive survey of the advancements in the preparation, functionalization, and modification of GAs in the context of battery research. It explores their application as electrodes and hosts for the dispersion of active material nanoparticles, resulting in the creation of hybrid electrodes for a wide range of rechargeable batteries including lithium-ion batteries (LIBs), Li-metal-air batteries, sodium-ion batteries (SIBs), zinc-ion batteries (AZIBs) and zinc-air batteries (ZABs), aluminum-ion batteries (AIBs) and aluminum-air batteries and other.

Highly Reactive Graphene Dispersant and Its Effective Reinforcement for Phase Change Coatings

High efficient dispersant that meanwhile possesses additional functions is highly desirable for the fabrication of graphene-based composite. In this paper, a new reactive dispersant, multi-silanols grafted naphthalenediamine (MSiND), is synthesized, which shows superiority compared with conventional dispersants. It can not only stabilize graphene in water at a high concentration of up to 16 mg mL-1, but also simultaneously be applicable for ethanol medium, in which the graphene concentration can be as high as 12 mg mL-1 at the weight ratio of 1:1 (MSiND:graphene). The dispersion is compatible with multi-matrixes and affinity to various substrates. In addition, MSiND exhibits excellent reactivity due to the existence of high-density silanol groups. Tough graphene coatings are constructed on glass slides and non-woven fabric simply by direct painting and dip-coating. Moreover, with the assistance of MSiND, graphene-doped phase-change coatings on hydrophobic non-woven fabric (e.g., functional mask) are prepared via the spray method. The composite coatings show enhanced mechanical strength and excellent energy storage performance, exhibiting great potential in heat preservation and thermotherapy.