Quasi-elastic Neutron Scattering Measurement of Hydrogen Diffusion in a Graphene Oxide Framework
Matthew J. Connolly, Z. N. Buck, Carlos Wexler, Joseph C. Schaeperkoetter, H. Taub, Andrew Gillespie, Helmut Kaiser
We present quasielastic neutron scattering (QENS) spectra from molecular hydrogen adsorbed in GOF. The measurements probed the motion of adsorbed hydrogen as a function of pressure, in order to understand the relationship between the motion of adsorbed molecules and the mechanism of pore expansion. Evidence of an increase in diffusion rates as a function of pressure are consistent with previously reported diffraction measurements of pore expansion in GOF materials. The quasielastic measurements were also able to detect rotational motions of the linker molecules in the solid GOF structure. A measurement of the rotational diffusion coefficient was made, as well as an estimate of the linker concentration.