This proposal aims to use small angle neutron scattering for characterization of hydrogen adsorption (including the provision of a quantitative value for the absolute hydrogen density) in nanoporous hydrogen storage materials at cryogenic temperatures and high pressures. We will collect SANS spectra from three well-characterised carbide-derived carbon materials having systematically increasing pore diameters at 77 K to obtain a direct measure of the densities of H2 adsorbed as a function of in-situ gas dosing pressure (up to 50 bar). In addition, we will use H/D contrast matching to obtain information on the mobility of the condensed phase. Finally, to ascertain whether adsorptive H2 densification is primarily a result of confinement or whether surface interactions play a significant role, the density of the hydrogen in a very high uptake MOF material will be measured.