Mechanically robust and electrically conductive carbon nanotube foams

We describe the fabrication of ultralow-density carbon nanotube (CNT) foams that simultaneously exhibit high electrical conductivities and robust mechanical properties. Our approach utilizes carbon nanoparticles as a binder to crosslink randomly oriented bundles of single-walled CNTs. The resulting CNT foams are the stiffest low-density nanoporous solids reported and exhibit elastic behavior up to strains as large as ∼80%. The use of the carbon binder also allows bulk electrical conductivity to be maintained at low densities.