Carbon nanofoam as a potential hydrogen storage material

Abstract

Hydrogen based fuel cells are considered to be an important future alternative to fossile based energy sources such as oil, natural gas and coal. For many applications such a hydrogen driven cars, the limiting factor is the weight of the hydrogen fuel storage device which seems to be excessive for hydrogen stored in metals. This is the reason for the search for ultralight hydrogen storage materials such as carbon nanotubes or graphite layers. Here we report on the investigation of the basic mechanism of H-carbonaceous interactions leading to hydrogen storage. The system has an ultra-low density of 2-10 mg/cm3 and a large surface area 300-400 m2/g. Electron diffraction showed the presence of hyperbolic "schwarzite" layers making the system suitable for hydrogen storage. Preliminary proton NMR experiments showed that hydrogen can indeed be reversibly stored in carbon nanofoam at room temperature and that the corresponding proton spin lattice relaxation time T1 of the stored hydrogen is 400 ms.