Substrate structure and dynamics effect on sorption properties : Theory and experiment||Substrate structure and dynamics effect on sorption properties : theory and experiment

Abstract

Adsorbent materials such as activated carbon and metal organic frameworks (MOFs) have received significant attention for their potential for storage of hydrogen and natural gas. Typically the adsorbent is assumed to consist of rigid slit-or cylindrical-shaped pores. Recent experimental adsorption measurements, however, suggest significant mechanical response breathing of the adsorbent in the presence of an adsorbate. In this thesis, I develop theoretical and computational models which predict high adsorbate densities in narrow carbon pores which give rise to a strong pressure on pore walls. I then present predictions of the mechanical response of the solid to this pressure, and the effect of this response on adsorption isotherms. Neutron scattering measurements of this mechanical response as well as the diffusion of the adsorbate in the breathing Graphene Oxide Framework (GOF) material is presented.In addition, calculations are presented which support a route toward enhancing the binding energy in carbonaceous adsorbates through boron doping via decaborane adsorption and subsequent decomposition.xx