Flexible metal-organic framework compounds: In situ studies for selective CO2 capture
Andrew J. Allen, Laura Espinal, Winnie K. Wong-Ng, Wendy Queen, Craig Brown, Steven R. Kline, Kristi L. Kauffman, Jeffrey T. Culp
Results from in situ experiments are presented to correlate carbon capture with dynamic structural changes in two flexible metal-organic framework (MOF) materials: porous coordination polymers (PCPs) exhibiting promising carbon dioxide adsorption/desorption properties. These properties arise from different internal ligand linker arrangements. Specifically, adsorption/desorption gas isotherm measurements are compared with in situ small-angle neutron scattering (SANS) and diffraction measurements of the associated structural changes, and complimentary wide-angle neutron and X-ray diffraction measurements. The prospects for improving each systems carbon capture functionality, including its selectivity for adsorbing CO2 from gas mixtures, are discussed with reference to a potential materials-by-design approach.