High sorption capacities and enhanced interaction strengths are the two most fundamental prerequisites for the deployment of carbon-based materials as hydrogen-storage media. In spite of continued research efforts over the two past decades, no substrate appears to meet these stringent requirements. We have identified a novel family of carbon-based nanostructures, so-called C-Mats, displaying very promising properties for hydrogen storage. Hydrogen uptake is as high as 2 wt % at 150K and moderate pressures below 15 bar. In addition, adsorption/desorption cycles are characterized by strong hysteresis effects following hydrogen loading. The aim of this proposal is to explore hydrogen adsorption in C-Mats by means of neutron spectroscopy (IRIS) and diffraction (NIMROD). These data will provide unprecedented insight into the adsorption mechanisms at play in this novel class of nanomaterials.