Elastic Recovery Properties of Ultralight Carbon Nanotube/Carboxymethyl Cellulose Composites.

Ultralight materials exhibit superelastic behavior depending on the selection, blending, and carbonization of the materials. Recently, ultimate low-density materials of 5 mg/cm or less have attracted attention for applications such as sensors, electrodes, and absorbing materials. In this study, we fabricated an ultralight material composed of single-walled carbon nanotubes (CNT) and sodium carboxymethyl cellulose (CMC), and we investigated the effect of density, composition, and weight average molecular weight of CMC on elastic recovery properties of ultralight CNT/CMC composites.

Light-induced levitation of ultralight carbon aerogels via temperature control.

We demonstrate that ultralight carbon aerogels with skeletal densities lesser than the air density can levitate in air, based on Archimedes' principle, when heated with light. Porous materials, such as aerogels, facilitate the fabrication of materials with density less than that of air. However, their apparent density increases because of the air inside the materials, and therefore, they cannot levitate in air under normal conditions.